your digital ID name cannot be found by the underlying security system

Dear Amin Qureshi,

Good day! Thank you for posting to Microsoft Community. We are happy to help you.

Based on your description, I understand that you have a concern “your digital ID name cannot be found by the underlying security system”. We are looking into the issue, however before we proceed, we need more detailed information about the situation you are experiencing.

Kindly share the following information with us:

1. What version of Outlook do you have? What version of Outlook do I have? (microsoft.com)
2. Which email account setting do you used, POP, IMAP, and SMTP settings (microsoft.com)?
3. Have you tried opening the file when the antivirus software disabled?
4. Have you tried run the outlook In safe mode?

Meanwhile, I suggest changing the Server Timeouts setting in Outlook, Switch off the Windows Firewall, End all Outlook-related processes in task manager and restart Outlook to see if any change happens. Furthermore, Go to File, click Options > Trust Center > Under Microsoft Outlook Trust Center, click Trust Center Settings, On the E-mail Security tab, under Encrypted e-mail, click Settings to make sure that you have chosen the correct certificate. Refer to Get a digital ID (microsoft.com).

We look forward to hearing from you. Thank you for your cooperation.   

Sincerely,

De Paul | Microsoft Community Moderator

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