Error when connecting to Exchange Online via Powershell

Question

Hi Guys,

for a few weeks now, we are getting an error when trying to connect to ExchangeOnline with the Powershell Console.
This question "https://learn.microsoft.com/en-us/answers/questions/912371/exchange-online-ps-error.html" is similar/equal to our problem, but so far it didnt work.
In the past our commands worked without problems, but suddenly it fails.
Here is a Screenshot of the Error and some other things I checked from the question above:

When I enter the this line "Connect-ExchangeOnline -UserPrincipalName admin@keyman .onmicrosoft.com" a microsoft window pops up and asks me for my password.
I enter the password and then i get the error message.

Do you guys have any tipps, that I should try?
If you need some more informations, just let me know.

Thanks

Answer 1

Hi, please try to make sure TLS 1.2 is enabled for the .Net Framework by checking/setting the following registry keys:

 Windows Registry Editor Version 5.00  
      
 [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v2.0.50727]  
 "SystemDefaultTlsVersions"=dword:00000001  
 "SchUseStrongCrypto"=dword:00000001  
      
 [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v4.0.30319]  
 "SchUseStrongCrypto"=dword:00000001  
 "SystemDefaultTlsVersions"=dword:00000001  

(ref. https://www.easy365manager.com/knowledgebase/aadsts1002016-you-are-using-tls-version-1-0-1-1-and-or-3des-cipher/)

Answer 2

Hi,

Please try using your real domain as the username rather than the onmicrosoft version. This could make a difference.

I hope this answers your question.

Thanks.

---

--If the reply is helpful, please Upvote and Accept as answer--

Answer 3

Hi,

thanks for your answers.
I will try the things I can do today.
I will give you an update once I am finished with testing.

UPDATE:
I tested with my personal Domainaccount, which is also member of "Global Administrator".
I get this error message:

Error Acquiring Token:
AADSTS1002016: You are using TLS version 1.0, 1.1 and/or 3DES cipher which are deprecated to improve the security postur
e of Azure AD. Your TenantID is: XXXXX. Please refer to https://go.microsoft.com/fwlink/?
linkid=2161187 and conduct needed actions to remediate the issue. For further questions, please contact your administrat
or.
Trace ID: a41687bc-XXXXX
Correlation ID: 7358ce47-dc12-4c2d-XXXXX
Timestamp: 2022-08-22 07:20:41Z
New-ExoPSSession : Mindestens ein Fehler ist aufgetreten.
In C:\Program
Files\WindowsPowerShell\Modules\ExchangeOnlineManagement\2.0.5\netFramework\ExchangeOnlineManagement.psm1:475
Zeichen:30

• ... PSSession = New-ExoPSSession -ExchangeEnvironmentName $ExchangeEnviro ...
• ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
• CategoryInfo : NotSpecified: (:) [New-ExoPSSession], AggregateException
• FullyQualifiedErrorId : System.AggregateException,Microsoft.Exchange.Management.ExoPowershellSnapin.NewExoPSSess
  ion

The command "Get-ExOMailbox" I cannot run, because it says:

Get-ExOMailbox : You must call Connect-ExchangeOnline before calling any other cmdlet.

The Basic Authentication is enabled.
And we do not use a proxy.
Security Defaults are in AAD disabled.
The Client where I am trying the connection from, is the Exchange Hybrid Server (Server 2016) itself.

Now the error message at least tells me something.
I will read the microsoft manuell and hope that I can fix the error this way.