This browser is no longer supported.
Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support.
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(128, 8%, 22%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EA%3C/text%3E%3C/svg%3E)
Hi,
Something went wrong [2400] error in outlook application. Web outlook is working fine.
Tried outlook repair, reinstallation, new profile creation and cleared password from device credential manager still issue persist. Seems like Microsoft issue. Screenshot attached
Please share any troubleshooting steps for permanent fix
Thanks
Anand
Using Classic Outlook on Windows for personal email, calendar, and contact management
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
I was having the same exact issue with Outlook this morning after an update from Microsoft. Emails where not working. Then I noticed the date and time was wrong in the task bar. I fixed that then restarted Outlook and it sync'd right up with my email and starting getting them again. hope this helps.
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.
Thanks a lot, this worked.
I have the same problem.
I have two accounts, but switching back and forth did not help me.
I only had a problem with ONE of the outlook accounts. The free one. (other is attached to 365)
Error 2400 - So, I have the same problem. I have two outlook/hotmail accounts, one attached to 365 and one is free. The free one isn't working anymore.
I m not ready to do all this reinstalling and registry stuff, cause its so much wasted time. Instead, I would prefer, that Microsoft is getting their sh*t together and make an update for that. This thread is long enough, that several people have that problem. And thats only the people, who made a post to this topic. I pretty sure MS broke something with the last update and now a lot of people with this account constellation have that problem.
This worked for me!
Brilliant
Just switching back and forth between accounts (I have 2 Exchange accounts) fixed it in 2 seconds.