Hi @Anand ,
Welcome to our forum!
What operation have you done then the issue occurred?
And what's the type of your account? (POP/IMAP/Exchange) If you are using an Exchange account, did you enable cache mode?
Considering that you have done several troubleshooting steps, it is suggested that you could try to create a new profile(Control Panel>Mail>Show Profiles>add) and add the account for testing to check if there are some differences.
In addition, i found a thread mentioned that it may be related to a registry, it's suggested that you could refer it: "Contacting the Server for Information" outlook pop up is coming up all of a sudden on every email with an attachment and/or links in a signature of someone on the chain.
(Note: Serious problems can occur if you modify the registry incorrectly. Before making changes, back up the registry to restore it in case something goes wrong.)
Hope to help you!
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