Getting 2400 error in outlook application

Hi Anand,

Good day.

Hope you are doing well. Thank you for posting in Microsoft Community.

According to your description, before moving forward, could you please allow me to collect below information to understand particular situation?

* If you open Outlook in safe mode, are you getting this error message?

* Please try to diagnose this situation via running Microsoft Support and Recovery Assistant tool. This tool may be help to diagnose Outlook related problems.

* Could you please provide me brief Office version screenshot page? To know this, open any Office 365 application such as Word / Excel / PowerPoint / Outlook > File > Office Account and share with me entire screenshot page via private message.

* On the other side, just for verification purpose, I would like to know if you are getting this situation on other Office applications such as Word / PowerPoint / Excel?

* Whether this situation has happened with any other users in your organization?

If you are getting any result via SARA tool, please try to provide that result in private message for further analysis.

Note: due to data privacy, please share with me above requested information in private message. I sent private message.

Here are the steps to open private messages:

To view private messaging options> click your profile picture at the top on the right > select the My Profile option.

I will look forward to your further response about above requested information in private message. Thank you for your precious time.

Stay safe and healthy.

Sincerely,

Darpan

Hi There

I am getting the same error. Its an irritation but doesnt stop me using the application.

I get the same error when opening in safe mode. Tried running ms support and recovery assistance and outlook wouldnt open at all.

Any ideas?

Matt

Same here. I started getting the same error after an update on Friday, April 14. I get authentication prompt and then the 2400 error. The account I'm being prompted for hasn't picked up any new emails since before the update.

I was also getting this error.

Attempted to use the Microsoft Support and Recovery Tool, and was exited on a screen that said it didn't support this type of account.

Account is current and up to date

Additional info: After you close the screen shown in Anand's original post, you get this.

Jinky Fix - Opened outlook from the Start Menu as Administrator (Right click on application and choose Run as Administartor), application opened and ran perfectly. Note: There were a couple more clicks after choosing to run as administrator... I don't remember what they were, but the are common sense answers.

It Works - Closed application and re-opened it from my pinned shortcut and application runs perfectly. Fixed for now!

Jay

I am having this same issue. I have multiple email accounts that I access through Outlook on my PC. One of them, an actual @outlook.com account, is repeatedly throwing this error. I believe it began after a Windows update. I have not been able to send/receive email on this one particular email account since 4/4/23 yet all of my other email accounts have been just fine. I have reset my password and I continue to send/receive emails on all accounts on my iPhone, but need to be able to do so on my PC, as well. I've also done a system restore to a point prior to the Windows update, but to no avail. I cannot use the Microsoft Support and Recovery Assistant tool as it tells me I am not eligible (?). Tried steps to log in as Administrator, however I still receive the same error message. Please advise asap as I need this account to function properly on my PC.

JH