Getting 2400 error in outlook application

This worked for me!

I tried all of the suggestions here and its still broken.

Why cant MS get their **** together?

Luckily my iPad mail app (NOT Outlook) still works, and its free. It has never had an issue.

I am so sick of dealing with the garbage this company puts out. Once this laptop dies, I'm going to get a Mac, and will NEVER come back.

Hey MS, you suck!

Also had the dreaded Error 2400 message with Outlook. None of the suggestions listed on here worked. Spent 2 hours with Microsoft remotely working on my computer & assistant could not fix it. Eventually all she could do was a workaround, creating a new profile on my PC & setting up a fresh version of Outlook on it. Works fine now, but a bit of a pain migrating everything else to the new profile. And, coincidentally or not, it all started after a windows update!

I had the same issue, but I managed to fix it.

On Outlook application, go to File > Office Account, check whether your affected email address is signed in under Account (on the left side).

If it is not, then try click Switch account and check whether your affected email address account is there.

Most likely it is not, just add and sign in and it should be fixed.

You can switch back to your original account after you added the affected email address account.

This solution fixed the problem for me too, thank you. After a week of trying all different solutions and giving up a couple of times, I finally found this solution and it seems to be working so far.

Katherine,

There is a service incident that is causing Outlook Web Access not to work, EX610644. You can track status on Twitter here, Microsoft 365 Status on Twitter: "We're investigating an Outlook for the web access issue affecting our customers in North America. Please refer to the Service Health Dashboard in the admin center under EX610644 for more details." / Twitter.