Credit to Arjon Sonnema Netherlands.

When you have an error:

The Action cannot be completed. The connection to Microsoft Exchange is unavailable. Outlook must be online or connected to complete this action

Solution:

Login a user with Administrative rights to the domain.

Run the scipt (LINK) Please rename .txt to .vbs and replace @yourdomain.com to the correct domain name!

 #Start

Set objSysInfo = CreateObject(“ADSystemInfo”)

Set objUser = GetObject(“LDAP://” & objSysInfo.UserName)
Set objComputer = GetObject(“LDAP://” & objSysInfo.ComputerName)

‘strMessage = objComputer.Description
‘strMessage = objComputer.Mail
strMessage = objUser.msExchMailboxGuid
strMessage = GuidToString(strMessage) &”@yourdomain.com”
WScript.Echo strMessage
Set objFileToWrite = CreateObject(“Scripting.FileSystemObject”).OpenTextFile(“d:\guid.txt”,2,true)
objFileToWrite.WriteLine(strMessage)
objFileToWrite.Close
Set objFileToWrite = Nothing

‘objUser.Description = strMessage
‘objUser.SetInfo

‘objComputer.Description = strMessage
‘objComputer.SetInfo

Function HexByte(b)
HexByte = Right(“0” & Hex(b), 2)
End Function

Function GuidToString(ByteArray)
Dim Binary, S
Binary = CStr(ByteArray)
‘ S = “{”
S = S & HexByte(AscB(MidB(Binary, 4, 1)))
S = S & HexByte(AscB(MidB(Binary, 3, 1)))
S = S & HexByte(AscB(MidB(Binary, 2, 1)))
S = S & HexByte(AscB(MidB(Binary, 1, 1)))
S = S & “-”
S = S & HexByte(AscB(MidB(Binary, 6, 1)))
S = S & HexByte(AscB(MidB(Binary, 5, 1)))
S = S & “-”
S = S & HexByte(AscB(MidB(Binary, 8, 1)))
S = S & HexByte(AscB(MidB(Binary, 7, 1)))
S = S & “-”
S = S & HexByte(AscB(MidB(Binary, 9, 1)))
S = S & HexByte(AscB(MidB(Binary, 10, 1)))
S = S & “-”
S = S & HexByte(AscB(MidB(Binary, 11, 1)))
S = S & HexByte(AscB(MidB(Binary, 12, 1)))
S = S & HexByte(AscB(MidB(Binary, 13, 1)))
S = S & HexByte(AscB(MidB(Binary, 14, 1)))
S = S & HexByte(AscB(MidB(Binary, 15, 1)))
S = S & HexByte(AscB(MidB(Binary, 16, 1)))
‘ S = S & “}”
GuidToString = S
End Function

#Stop

 You will have a file saved on D drive with a value like:

EA70C47D-309c-4ggg-111d-17A7386E9583@yourdomain.com

Save this for later

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