Version
6.6, not the version-specific
Issue Details
At the time of opening MC, an error message was appearing, "Connection timeout Expired. The timeout period elapsed during the post-login phase."
Below is the screenshot for the same:
Resolution
As per the error screenshot it is a connection issue. MC server is having connectivity issues with the Database server. So check and make sure that there is no connection issue between MC and DB server.
Once the connection will be restored the issue should be resolved.
This KB article concludes here.