Hi Langfield,

Please can on you confirm the version of CRM that you're using. 

This occurs in both 2018 R3 & 2020 R1.

This wasn't happening to the 2018R3 until now and I have a test VM with the same data of my 2020 R1 machine that does work.

Is there any thing special about the Exchange Server 'trusting' VM #1 and not VM #2? 

Could be a red herring, I'm not an Exchange person, but in the past when configuring CRM with Exchange one of the most common problems I've come across is the IT Dept not having 'trusted' the server on which CRM is installed. Admittedly this is a slightly different error message but might be worth looking it to just in it's something similar. 

Is there any thing special about the Exchange Server 'trusting' VM #1 and not VM #2? 

Could be a red herring, I'm not an Exchange person, but in the past when configuring CRM with Exchange one of the most common problems I've come across is the IT Dept not having 'trusted' the server on which CRM is installed. Admittedly this is a slightly different error message but might be worth looking it to just in it's something similar. 

Thanks Matthew, I'll run this by IT and see what they say.

Hi

Can you please share your solution? I'm having the same problem in 2023R1, one VM works, another one doesn't.

Thank

Bea