Forum Discussion
Gmail sync issues within Outlook Classic
Yesterday, my Gmail folders stopped or failed to sync within Outlook Classic. I went through a number of steps including removing the account, re-adding it but now the sub-folders have disappeared completely. Every time I launch Outlook Classic, there is a Send/Receive Error.
I have for now started using the new version of Outlook of which all the Gmail folders are present. However, this new version never allowed (and still does not allow) you to add additional email accounts. It says you don’t have permission to, etc…
As a result of errors and issues with both versions of Outlook, I am having to use Outlook Classic for work (M365) email accounts and the new Outlook for my Gmail account. This is absurd .
I have seen that this appears to be a recent and known issue with Outlook Classic and looks to being investigated. But why and how did this even happen in the first place? Who at Microsoft has decided to implement a change or update which has impacted a large volume of customers all over the world!?!
Hi, there is a global security update that is changing the credentials for your Gmail account with Outlook Classic. You need to do two things: Here is the link on how to do it from the Microsoft site. I'd skip down to the manual fixes:
7 Replies
Hornblower409 is right, there are a few things that be a problem I have found in the past few weeks. Comcast and Yahoo are really having a good old go at it. Deeper registry key deletions than normal. I have had to delete one reg key for a Gmail issue that not using the standard repair.
Hi, there is a global security update that is changing the credentials for your Gmail account with Outlook Classic. You need to do two things: Here is the link on how to do it from the Microsoft site. I'd skip down to the manual fixes:
It works on one computer with a still-active Gmail account in Outlook, but not when a Gmail account is removed (on the second computer). I have deleted the OAuth lines from the registry on both machines, but I still get this error when trying to add a Gmail account. I think the reason might be connected with access to localhost (connection to localhost:8011 was reset):
This is the last step of the procedure. Antivirus turns off, doesn't help. Of course, I have checked access to Gmail for Microsoft Apps.
This process did not resolve the issue...
This process did not resolve the issue...
I have a writeup on this issue I call "Start From Scratch". Some people have found that this works when the quick workarounds from Microsoft Support don't.
See the answer by "Hornblower409 Mar 19, 2026, 12:37 AM" at
Pay particular attention to Step 1
Export any data for the GMail account that you have stored only locally in "This Computer Only" folders. Since the OST file it is stored in will be useless once you remove the account.
If that doesn't fix it for you, come back and we'll look for something else. After all, this is Outlook, there are lots of different ways it can go sideways that have nothing to do with cached OAuth credentials.
Oh my gawd, that is it. Problem solved. Thank you!
DevilDamo Great news! Glad it helped! If anyone else is still having an issue, you might need to make sure you are logged into Gmail online and your browser is set to default to Chrome. That's the trick I learned with the 365 apps. You can switch back after connecting.
