diff --git a/Beispielprojekt/Connect-Webservice.ps1 b/Beispielprojekt/Connect-Webservice.ps1
index 1e0f89de4c29a99728977abbe399b87e80a92fb4..544e0cc3153f518c36833ade522c365e1332d90c 100644
--- a/Beispielprojekt/Connect-Webservice.ps1
+++ b/Beispielprojekt/Connect-Webservice.ps1
@@ -11,7 +11,7 @@ function Connect-WebService # Verbinden mit dem WebServices
     $Cred = New-Object System.Management.Automation.PSCredential -ArgumentList $Username, $PwdSecureString
     
     # Mit API verbinden
-    $uri = "https://ws.rc.rwth-ad.de/ex-cache-ws/APIv05_1.asmx?WSDL"
+    $uri = "https://ws.rc.rwth-ad.de/ex-cache-ws/APIv04.asmx?WSDL"
     
     
     # Hier wird eine Do-Schleife verwendet, weil das verbinden mit dem ws.rwth-ad.de manchmal nicht klappt
diff --git a/PesterTests/MailAdm-Doku.Tests.ps1 b/PesterTests/MailAdm-Doku.Tests.ps1
index e8023d7b92a0be821d6fe11225c92fe4f3fc0f3c..df47a840fe2359eb7706d73f419b0671f24bd2b2 100644
--- a/PesterTests/MailAdm-Doku.Tests.ps1
+++ b/PesterTests/MailAdm-Doku.Tests.ps1
@@ -1,18 +1,18 @@
 # These are the Pester Tests in order to demonstrate how the API works and 
-# reflects the following versions API05_1 MailADM 3.0.4
+# reflects the following versions API04 MailADM 3.0.3
 # If you need further documentation please check our doku-portal [0]
 # or contact our IT-ServiceDesk (servicedesk@itc.rwth-aachen.de)
-# [0] https://help.itc.rwth-aachen.de/service/1jefzdccuvuch/article/31c9d912142143d0a9740fa5e55f9701
+# [0] https://doc.itc.rwth-aachen.de/dosearchsite.action?queryString=MailAdm
 
 # initializing
 # connection settings
-$user = "srv129521@rwth-ad.de" # e.g. srv123456@rwth-ad.de
-$password = "NT62o96Zg33oH6GFjh"
-$uri = "https://ws.rwth-ad.de/ex-cache-ws/APIv05_1.asmx?wsDL"
+$user = "<Service Account>" # e.g. srv123456@rwth-ad.de
+$password = "<Password>"
+$uri = "https://ws.rwth-ad.de/ex-cache-ws/APIv04.asmx?wsDL"
 
 # set variables
 # please change the following variables
-$existingUPN = "lg802991@mustereinrichtung.rwth-aachen.de" # e.g. ab123456@mustereinrichtung.rwth-aachen.de
+$existingUPN = "<existing user logon name>" # e.g. ab123456@mustereinrichtung.rwth-aachen.de
 
 # these variables should work
 $Primarydomain = "mustereinrichtung.rwth-aachen.de"
@@ -22,15 +22,15 @@ $existingfunctionalMailbox = "rudirentier@mustereinrichtung.rwth-aachen.de"
 $externalmailaddress = "hugo@mueller.de"
 $localpartpersonalmailmox = "hugodertierpfleger"
 $distributionlist = "zoo@mustereinrichtung.rwth-aachen.de"
-$seconddistributionlist = "tiergehege@mustereinrichtung.rwth-aachen.de"
 $newdistributionmailaddress = "alletiere2@mustereinrichtung.rwth-aachen.de"
 $newmailaddress = "zebra@mustereinrichtung.rwth-aachen.de"
 
 # import functions
-. "C:\temp\MailADM-API\mailadm-api\PesterTests\connect.ps1"
-. "C:\temp\MailADM-API\mailadm-api\PesterTests\listquota.ps1"
-. "C:\temp\MailADM-API\mailadm-api\PesterTests\mailaccounts.ps1"
-. "C:\temp\MailADM-API\mailadm-api\PesterTests\distributionlist.ps1"
+. .\connect.ps1
+. .\listquota.ps1
+. .\mailaccounts.ps1
+. .\distributionlist.ps1
+
 
 
 
@@ -66,7 +66,7 @@ Describe "MailAdm-Doku" {
 
     It "Remove-Mailboxinvitation: dummy test in order to remove all invitations to get a defined infrastructure" {
         $result = remove-allmailboxinvitation -webserviceconnection $global:ws
-        # check if all invitations could be deleted
+        # check if alll invitations could be deleted
         $invitations = get-mailboxinvitations -webserviceconnection $global:ws
         $invitations.count | should -Be 0
     }
@@ -76,7 +76,6 @@ Describe "MailAdm-Doku" {
         $givenname = "Hugo"
         $primaryMailaddress = "$localpartpersonalmailmox@$Primarydomain"
         $MailaddressAliasList = @()
-        $DistributionGroupAddresses = @()
         $quota = 10
         # Mailboxtype:
         # 0 : personal mailbox
@@ -91,7 +90,7 @@ Describe "MailAdm-Doku" {
         $quotapool = get-quotapool -Domain mustereinrichtung.rwth-aachen.de -WebServiceConnection $global:ws                                                           
         [int32]$quotapoolid = $quotapool[0].id
 
-        $invitation = add-mailboxinvitation -webserviceconnection $global:ws -quotaPoolID $quotapoolid -primaryEMailAddress $primaryMailaddress -givenname $givenname -surname $Surname -QuotaInMB $quota -Aliasaddresses $MailaddressAliasList -DistributionGroupAddresses $DistributionGroupAddresses -Mailboxtype $Mailboxtype -DeliverToMailBoxAndforward $DeliverMailboxAndForward -ForwardingEmailaddress $ForwardingEmailaddress -Owner $Owner
+        $invitation = add-mailboxinvitation -webserviceconnection $global:ws -quotaPoolID $quotapoolid -primaryEMailAddress $primaryMailaddress -givenname $givenname -Surname $surname -QuotaInMB $quota -Aliasaddresses $MailaddressAliasList -Mailboxtype $Mailboxtype -DeliverToMailBoxAndforward $DeliverMailboxAndForward -ForwardingEmailaddress $ForwardingEmailaddress -Owner $Owner
         $invitation.returncode | should -Be 0
     }
 
@@ -100,7 +99,6 @@ Describe "MailAdm-Doku" {
         $givenname = ""
         $primaryMailaddress = "zooleitung@$Primarydomain"
         $MailaddressAliasList = @()
-        $DistributionGroupAddresses = @()
         $quota = 10
         # Mailboxtype:
         # 0 : personal mailbox
@@ -115,7 +113,7 @@ Describe "MailAdm-Doku" {
         $quotapool = get-quotapool -Domain mustereinrichtung.rwth-aachen.de -WebServiceConnection $global:ws                                                           
         $quotapoolid = $quotapool[0].id
 
-        $invitation = add-mailboxinvitation -webserviceconnection $global:ws -quotaPoolID $quotapoolid -primaryEMailAddress $primaryMailaddress -givenname $givenname -Surname $surname -QuotaInMB $quota -Aliasaddresses $MailaddressAliasList -DistributionGroupAddresses $DistributionGroupAddresses -Mailboxtype $Mailboxtype -DeliverToMailBoxAndforward $DeliverMailboxAndForward -ForwardingEmailaddress $ForwardingEmailaddress -Owner $Owner
+        $invitation = add-mailboxinvitation -webserviceconnection $global:ws -quotaPoolID $quotapoolid -primaryEMailAddress $primaryMailaddress -givenname $givenname -Surname $surname -QuotaInMB $quota -Aliasaddresses $MailaddressAliasList -Mailboxtype $Mailboxtype -DeliverToMailBoxAndforward $DeliverMailboxAndForward -ForwardingEmailaddress $ForwardingEmailaddress -Owner $Owner
         $invitation.returncode | should -Be 0
     }
 
@@ -124,7 +122,6 @@ Describe "MailAdm-Doku" {
         $givenname = ""
         $primaryMailaddress = "eisbaergehege@$Primarydomain"
         $MailaddressAliasList = @()
-        $DistributionGroupAddresses = @()
         $quota = 10
         # Mailboxtype:
         # 0 : personal mailbox
@@ -139,7 +136,7 @@ Describe "MailAdm-Doku" {
         $quotapool = get-quotapool -Domain mustereinrichtung.rwth-aachen.de -WebServiceConnection $global:ws                                                           
         $quotapoolid = $quotapool[0].id
 
-        $invitation = add-mailboxinvitation -webserviceconnection $global:ws -quotaPoolID $quotapoolid -primaryEMailAddress $primaryMailaddress -givenname $givenname -Surname $surname -QuotaInMB $quota -Aliasaddresses $MailaddressAliasList -DistributionGroupAddresses $DistributionGroupAddresses -Mailboxtype $Mailboxtype -DeliverToMailBoxAndforward $DeliverMailboxAndForward -ForwardingEmailaddress $ForwardingEmailaddress -Owner $Owner
+        $invitation = add-mailboxinvitation -webserviceconnection $global:ws -quotaPoolID $quotapoolid -primaryEMailAddress $primaryMailaddress -givenname $givenname -Surname $surname -QuotaInMB $quota -Aliasaddresses $MailaddressAliasList -Mailboxtype $Mailboxtype -DeliverToMailBoxAndforward $DeliverMailboxAndForward -ForwardingEmailaddress $ForwardingEmailaddress -Owner $Owner
         $invitation.returncode | should -Be 0
     }
 
@@ -148,7 +145,6 @@ Describe "MailAdm-Doku" {
         $givenname = ""
         $primaryMailaddress = "knutsspielzeug@$Primarydomain"
         $MailaddressAliasList = @()
-        $DistributionGroupAddresses = @()
         $quota = 10
         # Mailboxtype:
         # 0 : personal mailbox
@@ -163,7 +159,7 @@ Describe "MailAdm-Doku" {
         $quotapool = get-quotapool -Domain mustereinrichtung.rwth-aachen.de -WebServiceConnection $global:ws                                                           
         $quotapoolid = $quotapool[0].id
 
-        $invitation = add-mailboxinvitation -webserviceconnection $global:ws -quotaPoolID $quotapoolid -primaryEMailAddress $primaryMailaddress -givenname $givenname -Surname $surname -QuotaInMB $quota -Aliasaddresses $MailaddressAliasList -DistributionGroupAddresses $DistributionGroupAddresses -Mailboxtype $Mailboxtype -DeliverToMailBoxAndforward $DeliverMailboxAndForward -ForwardingEmailaddress $ForwardingEmailaddress -Owner $Owner
+        $invitation = add-mailboxinvitation -webserviceconnection $global:ws -quotaPoolID $quotapoolid -primaryEMailAddress $primaryMailaddress -givenname $givenname -Surname $surname -QuotaInMB $quota -Aliasaddresses $MailaddressAliasList -Mailboxtype $Mailboxtype -DeliverToMailBoxAndforward $DeliverMailboxAndForward -ForwardingEmailaddress $ForwardingEmailaddress -Owner $Owner
         $invitation.returncode | should -Be 0
     }
 
@@ -207,14 +203,10 @@ Describe "MailAdm-Doku" {
     }
 #>
 
-<#
-
-    # Es gibt in Version 05_1 keine Moeglichkeit mehr, Weiterleitungsadressen zu konfigurieren.
     It "change: forwardingaddress" {
         $result = change-mailboxforwardingaddress -webserviceconnection $global:ws -mailbox $existingfunctionalMailbox -newforwardingmailaddress $externalmaladdress
         $result | should -Be $true
     }
-#>
 
     It "change: emailaddresses" {
         $result = change-emailaddresses -webserviceconnection $global:ws -mailbox $existingPersonalMailaccount -primaryEmailaddress $existingPersonalMailaccount -secondaryemailaddress $newmailaddress
@@ -231,9 +223,9 @@ Describe "MailAdm-Doku" {
         # get mailboxinformation
 
         $mailboxes = $global:ws.getMailboxList()
-        $mailboxtochange = $mailboxes | Where-Object { $_.emailaddress -like $existingfunctionalMailbox }
+        $mailboxtochange = $mailboxes | ? { $_.emailaddress -like $existingfunctionalMailbox }
         $quotapoolIds = get-quotapool -Domain $Primarydomain -WebserviceConnection $global:ws
-        $quotapoolid = ($quotapoolIds | Where-Object { $_.id -ne $($mailboxtochange.quotapool.id) } | Select-Object -first 1).id
+        $quotapoolid = ($quotapoolIds | ? { $_.id -ne $($mailboxtochange.quotapool.id) } | select -first 1).id
 
         $result = change-mailboxquotapool -webserviceconnection $global:ws -mailbox $($mailboxtochange.upn) -newquotapool $quotapoolid
         $result | should -Be $true
@@ -269,8 +261,6 @@ Describe "MailAdm-Doku" {
         # 1	Funktionsaccount (in Exchange: UserMailbox)
         # 2	RoomMailbox
         # 3	EquipmentMailbox
-        # Der Vollzugriff ist eine notwendige Voraussetzung für das Wandeln in eine Ressourcen-Mailbox
-        change-addfullaccesspermission -webserviceconnection $global:ws -mailbox $existingfunctionalMailbox -user $existingPersonalMailaccount
         $upn = "fkt_$existingfunctionalmailbox"
         $result = change-mailboxtype -webserviceConnection $global:ws -upn $upn -newmailboxtype 2
         $result | should -Be $true
@@ -305,21 +295,13 @@ Describe "MailAdm-Doku" {
         # 3	EquipmentMailbox
         $upn = "fkt_$existingfunctionalmailbox"
         $result = change-mailboxtype -webserviceConnection $global:ws -upn $upn -newmailboxtype 0
-        # Der Vollzugriff wird für den nächsten Skriptdurchlauf entfernt
-        change-removefullaccesspermission -webserviceconnection $global:ws -mailbox $existingfunctionalMailbox -user $existingPersonalMailaccount
         $result | should -Be $false
     }
 
     It "create: distribution list" {
         $displayname = "Zoo"
-        $dl = create-distributionlist -WebserviceConnection $global:ws -displayname $displayname -mailaddress $distributionlist
-        $dl | should -Be 0
-    }
-
-    It "create: second distribution list" {
-        $secondlistdisplayname = "Tiergehege"
-        $dl = create-distributionlist -WebserviceConnection $global:ws -displayname $secondlistdisplayname -mailaddress $seconddistributionlist
-        $dl | should -Be 0
+        $distributionlist = create-distributionlist -WebserviceConnection $global:ws -displayname $displayname -mailaddress $distributionlist
+        $distributionlist | should -Be 0
     }
 
     It "Get distribution list" {
@@ -343,38 +325,23 @@ Describe "MailAdm-Doku" {
         $result | should -Be $true
     }
 
-    It "change: Distributionlist Mailaddress" {
+    It "cahnge: Distributionlist Mailaddress" {
         $result = change-distributionlistemailaddresses -WebserviceConnection $global:ws -mailaddress $distributionlist -newmailaddress $newdistributionmailaddress
         $($result.Returncode) | should -Be 0
     }
 
-    It "add member mailbox to distributionlist" {
-        $result = add-distributiongroupmember -WebserviceConnection $global:ws -maillistEMail $distributionlist -newmember $existingfunctionalMailbox
-        $result.Returncode | Should -Be 0
-    }
-
-    It "add member maillist to distributionlist" {
-        $result = add-distributiongroupmember -WebserviceConnection $global:ws -maillistEMail $distributionlist -newmember $seconddistributionlist
+    It "add member to distributionlist" {
+        $result = add-distributiongroupmember -WebserviceConnection $global:ws -distributionlist $distributionlist -newmember $existingfunctionalMailbox
         $result.Returncode | Should -Be 0
     }
 
-    It "remove member mailbox from distributionlist" {
-        $result = remove-distributiongroupmember -WebserviceConnection $global:ws -maillistEMail $distributionlist -member $existingfunctionalMailbox
-        $result.ReturnCode | Should -Be 0
-    }
-
-    It "remove member maillist from distributionlist" {
-        $result = remove-distributiongroupmember -WebserviceConnection $global:ws -maillistEMail $distributionlist -member $seconddistributionlist
+    It "remove member from distributionlist" {
+        $result = remove-distributiongroupmember -WebserviceConnection $global:ws -distributionlist $distributionlist -member $existingfunctionalMailbox
         $result.ReturnCode | Should -Be 0
     }
 
-    It "delete first distribution list" {
+    It "delete distribution list" {
         $result = remove-distributionlist -WebserviceConnection $global:ws -mailaddress $distributionlist
         $result | Should -Be $true
     }
-
-    It "delete second distribution list" {
-        $result = remove-distributionlist -WebserviceConnection $global:ws -mailaddress $seconddistributionlist
-        $result | Should -Be $true
-    }
 }
\ No newline at end of file
diff --git a/PesterTests/distributionlist.ps1 b/PesterTests/distributionlist.ps1
index 51fc0afa0cdfbb4f014e5ff7f952dd726631e103..12991cdf22ca3167ecd7fa5d308031f426006ced 100644
--- a/PesterTests/distributionlist.ps1
+++ b/PesterTests/distributionlist.ps1
@@ -13,7 +13,7 @@ function get-distributionlist {
     param ($WebserviceConnection, $mailaddress)
 
     $distributionlists = $WebserviceConnection.getMailLists()
-    $distributionlist = $distributionlists | Where-Object { $_.emailaddress -match $mailaddress }   
+    $distributionlist = $distributionlists | ? { $_.emailaddress -match $mailaddress }   
     
     $distributionlist
 }
@@ -23,9 +23,9 @@ function remove-distributionlist {
     param ($WebserviceConnection, $mailaddress)
 
     $distributionlists = $WebserviceConnection.getMailLists()
-    $groupSamAccountName = $distributionlists | Where-Object { $_.emailaddress -match $mailaddress }   
+    $distributionlist = $distributionlists | ? { $_.emailaddress -match "Zoo@mustereinrichtung.rwth-aachen.de" }   
 
-    $result = $WebserviceConnection.RemoveMailList($groupSamAccountName.SamAccountName)
+    $result = $WebserviceConnection.RemoveMailList($distributionlist.SamAccountName)
     $result
 }
 
@@ -73,30 +73,22 @@ function change-distributionlistdisplayname {
 
 function add-distributiongroupmember {
     [CmdletBinding()]
-    param ($WebserviceConnection, $maillistEMail, $newmember)
+    param ($WebserviceConnection, $distributionlist, $newmember)
 
-    $global:mailboxes = $webserviceconnection.getMailboxList()
-    $global:SamAccountName = $mailboxes | Where-Object {$_.emailaddress -like $newmember} | Select-Object -Property SamAccountName
-    if (!($mailboxes | Where-Object {$_.emailaddress -like $newmember})){
-        $global:maillists = $WebserviceConnection.getMailLists()
-        $global:SamAccountName = $maillists | Where-Object {$_.emailaddress -like $newmember} | Select-Object -Property SamAccountName
-    }
+    $mailboxes = $webserviceconnection.getMailboxList()
+    $mailbox = $mailboxes | ? { $_.emailaddress -like $newmember }
 
-    $result = $WebserviceConnection.addMemberToMaillist($maillistEMail, $SamAccountName.SamAccountName)
+    $result = $WebserviceConnection.addMailboxToMaillist($distributionlist, $mailbox.upn)
     $result
 }
 
 function remove-distributiongroupmember {
     [CmdletBinding()]
-    param ($WebserviceConnection, $maillistEMail, $member)
+    param ($WebserviceConnection, $distributionlist, $member)
 
-    $global:mailboxes = $webserviceconnection.getMailboxList()
-    $global:SamAccountName = $mailboxes | Where-Object {$_.emailaddress -like $member} | Select-Object -Property SamAccountName
-    if (!($mailboxes | Where-Object {$_.emailaddress -like $member})){
-        $global:maillists = $WebserviceConnection.getMailLists()
-        $global:SamAccountName = $maillists | Where-Object {$_.emailaddress -like $member} | Select-Object -Property SamAccountName
-    }
+    $mailboxes = $webserviceconnection.getMailboxList()
+    $mailbox = $mailboxes | ? { $_.emailaddress -like $member }
 
-    $result = $WebserviceConnection.RemoveMemberFromMaillist($maillistEMail, $SamAccountName.SamAccountName)
+    $result = $WebserviceConnection.RemoveMailboxFromMaillist($distributionlist, $mailbox.upn)
     $result
 }
\ No newline at end of file
diff --git a/PesterTests/mailaccounts.ps1 b/PesterTests/mailaccounts.ps1
index 519f469c5bff9f6477db2d7d72e51edf16ef1ea0..530ef7e89c99a69dbb80049ee978dc61ed038b2b 100644
--- a/PesterTests/mailaccounts.ps1
+++ b/PesterTests/mailaccounts.ps1
@@ -18,9 +18,9 @@ function get-mailbox {
 
 function add-mailboxinvitation {
     [CmdletBinding()]
-    param ($webserviceconnection, $quotaPoolID, $primaryEMailAddress, $givenname, $Surname, $QuotaInMB, $Aliasaddresses, $DistributionGroupAddresses, $Mailboxtype, $DeliverToMailBoxAndforward, $ForwardingEmailaddress, $Owner)
+    param ($webserviceconnection, $quotaPoolID, $primaryEMailAddress, $givenname, $Surname, $QuotaInMB, $Aliasaddresses, $Mailboxtype, $DeliverToMailBoxAndforward, $ForwardingEmailaddress, $Owner)
 
-    $invitation = $webserviceconnection.CreateMailaccountInvitation($quotaPoolID, $primaryEMailAddress, $givenname, $Surname, $QuotaInMB, $Aliasaddresses, $DistributionGroupAddresses, $Mailboxtype, $DeliverToMailBoxAndforward, $ForwardingEmailaddress, $Owner)
+    $invitation = $webserviceconnection.CreateMailaccountInvitation($quotaPoolID, $primaryEMailAddress, $givenname, $Surname, $QuotaInMB, $Aliasaddresses, $Mailboxtype, $DeliverToMailBoxAndforward, $ForwardingEmailaddress, $Owner)
     $invitation
 }
 
@@ -65,8 +65,6 @@ function reconnect-mailbox {
     $result
 }
 
-<#
-# Es gibt in Version 05_1 keine Moeglichkeit mehr, Weiterleitungsadressen zu konfigurieren.
 function change-mailboxforwardingaddress {
     [cmdletbinding()]
     param($webserviceconnection, $mailbox, $newforwardingmailaddress)
@@ -75,7 +73,6 @@ function change-mailboxforwardingaddress {
     $result = $webserviceconnection.setMailForwarding($mailboxtochange.upn, $true, $newforwardingmailaddress)
     $result
 }
-#>
 
 
 function change-mailboxquota {    
@@ -124,7 +121,7 @@ function change-mailboxdisplayname {
     $mailboxes = $webserviceconnection.getMailboxList()
     $mailboxtochange = $mailboxes | ? { $_.emailaddress -like $mailbox }
 
-    $result = $webserviceconnection.SetMailboxDisplayName($mailboxtochange.upn, $newdisplayname)
+    $result = $webserviceconnection.SetRessourceMailboxDisplayName($mailboxtochange.upn, $newdisplayname)
     $result
 }