How can I troubleshoot slow Outlook Online Mode on a terminal server?
We have an offsite terminal server that has always used Outlook Classic in Online Mode, so switching to Cached Mode is currently not practical. For roughly the past…
Outlook Classic
What are the best alternatives for managing a very large delegated calendar?
Our dean's assistant manages the dean's Microsoft 365 calendar through delegated access in Outlook Classic. The calendar and mailbox data total more than 7 GB, and Outlook frequently…
Is Outlook search failing for anyone else in the UK?
A small number of users are currently unable to search in Outlook. The problem occurs in Outlook on the web, the new desktop app, and classic Outlook, usually…
Voicemail MP3 Attachments Missing in Outlook Classic but Appear When Forwarded
Several users, including me, are seeing a strange issue with voicemail emails in classic Outlook. The message shows a paperclip, but the MP3 attachment itself is missing from…
How can I keep Outlook Classic usable with an 80GB Microsoft 365 mailbox?
I'm troubleshooting a user with a 100GB Microsoft 365 mailbox that is currently using about 80GB. Outlook Classic reaches the local OST size limit when configured for Cached…
How can I keep Outlook Classic usable with an 80GB Microsoft 365 mailbox?
I'm troubleshooting a Microsoft 365 user whose 100GB mailbox is already about 80GB full. Outlook Classic reaches the practical 40–50GB OST limit when cached mode is set to…
Issues with Passkey Login in Outlook Classic - What's Going On?
I recently started using Passkey with some customers, and everything was running smoothly with various devices like Windows Hello for Business and Microsoft Authenticator. However, I've encountered a…
How Can I Force Everyone to Use New Outlook and Disable Classic?
Hey everyone! I need some help with a situation at work. We're trying to stop users from accessing Outlook Classic because our CRM integration just isn't compatible with…
What’s going on with Outlook Classic? Are there known issues?
I've been hearing from various users that they've been having inconsistent problems with Outlook Classic under M365, particularly receiving the error message *"Information Store could not be opened."*…