Using Outlook (Classic) to set up sync from one email account to gmail online calendar

Question

I have a paid subscription to MS Office 365 from a work account. I used one of the 5 installation credits to load Office on my home computer. I added 2 email accounts I use as a consultant to Outlook (Classic) and my gmail account. I set all of these to IMAP.

On the previous installation of Outlook on the previous computer, I had the 2 consultant accounts set to POP and the gmail and work account to IMAP. I used gSyncit to sync just calendar and contacts to my google account so I can see the current calendar 24/7 when I am on the road.<<

I have my calendar details in one of the consultant accounts (e.g., [Moderator note: personal info removed]@XX.com). I was able in the previous PC installation to set that account in Outlook (Classic) email account settings as the default email, but it will not allow me to set the data file matching that account - which contains my calendar and contact details - to default. When I try, I get this error:

Can you tell me how to change settings in Outlook (Classic) to achieve what it was doing on my previous PC? If I need to switch the 2 consulting accounts to POP again for this to work, I can do that. I did not know this would make such a huge difference.

Thanks in advance!!

Answer 1

Dear @LBRT,

Thank you for posting your question in the Microsoft Q&A forum.

I understand how confusing this is, especially since the same setup worked on your previous computer. On your previous PC, the key difference was that your consulting accounts were configured as POP. POP accounts use .pst files, and PST files can be set as the default data file. That allowed your calendar and contacts to live in a local PST and sync correctly with Google via gSyncit. ​‌

However, in this case, what you’re seeing in Outlook (Classic) is expected behavior by design. In your current setup, your Microsoft 365 work account is an Exchange account, and your consulting accounts are configured as IMAP. When an Exchange account exists in the Outlook profile, Outlook does not allow an IMAP (.ost) data file to be set as the default data file. This is why you receive the error when trying to change the default mail delivery location.

If you actually want to use these accounts in one Outlook profile and change the default data files, as a workaround, you can try to add your exchange account again and turn off your cached exchange mode in the control panel when you just add your exchange account. For more information, please check this article: https://www.slipstick.com/outlook/change-the-default-data-file-from-exchange-to-another-account/

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Please understand that as a forum moderator, my role is to provide general guidance and troubleshooting support. I don’t have access to internal systems or backend tools, and I appreciate your understanding of these limits.

I hope the information shared helps point you in the right direction. Please try the steps above and let me know if they work. If not, we can continue working together to narrow this down.

The first response may not always resolve the issue right away, but with your help and more details, we can work toward a solution.

Thank you for your patience and understanding. I'm looking forward for your reply.

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