Hi @新鑫 刘 ,
Welcome to our forum!
How did you import contacts and old emails from the Main Identity folder of Outlook 2011? Import from a .olm file?
As I know, if we want to upgrade from Outlook for Mac 2011 to Outlook for Mac 365, we need to first export emails, contacts and other data to a .olm file first, so that we can import it to Outlook for Mac 365. This is consistent with what your distributor said.
For more information about exporting and importing, please refer to the following article:
Export to a .olm file: Export items to an archive file in Outlook for Mac
Import a .olm file: Import a .olm file from Outlook for Mac
And I noticed that your can not start Outlook 2011 anymore, is there any error reported? I'm afraid you need Outlook for Mac 2011 to start normally before exporting data.
As I know, support for Office for Mac 2011 ended on October 10, 2017, so I can't test it in my environment. Based on my research, I found a thread mentioned that this issue may be solved by rebuilding the Outlook database, it's suggested that you could try the method. For more information, please refer to: Outlook for Mac 2011 Won't Start.
Hope the above help!
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