Excel HTTP Error 400. The size of the request headers is too long

Anonymous
2024-01-25T17:23:24+00:00

Good afternoon,

Today I was helping a user, Alice, change a picture in the header of an excel workbook. When Alice clicks the "picture" button in the ribbon under the "Header and footer" tab, instead of showing the dialog to pick a file to insert, the window that pops up says "HTTP Error 400. The size of the request headers is too long" with no other information.

Notably, if Bob, another user with an apparently identical account and user profile, tries to follow the same steps on the same computer as Alice, Bob is able to do so without receiving the error message.

We have tried the following:

Reinstall office365

Sign out of user account and back in

Split the document into smaller documents in case it was a file size issue

Running the repair tool for office365

Thank you!

Edit:

Good morning! I am happy to say we found a solution! Unfortunately it was to reinstall Windows.

Microsoft 365 and Office | Excel | For business | Windows

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Anonymous
2024-02-01T11:11:15+00:00

Good afternoon,

Today I was helping a user, Alice, change a picture in the header of an excel workbook. When Alice clicks the "picture" button in the ribbon under the "Header and footer" tab, instead of showing the dialog to pick a file to insert, the window that pops up says "HTTP Error 400. The size of the request headers is too long" with no other information.

Notably, if Bob, another user with an apparently identical account and user profile, tries to follow the same steps on the same computer as Alice, Bob is able to do so without receiving the error message.

We have tried the following:

Reinstall office365

Sign out of user account and back in

Split the document into smaller documents in case it was a file size issue

Running the repair tool for office365

Thank you!

the following solution is also possible:

file - account - settings management - turn off optional online functions and done

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  1. Anonymous
    2024-04-16T20:02:18+00:00

    Solution I found that works is to go to Account, Manage Settings, Turn "off" optional connected experiences.

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  2. Anonymous
    2024-04-30T12:37:05+00:00

    Anyone know if Microsoft plans to fix this? It's been almost 4 months. My users are not happy about having to jump through hoops every time they want to add the company logo (from a local file) to a header/footer. Used to work fine until an update was pushed out. The behavior is also very inconsistent. You can uncheck that optional connected experiences but it doesn't always fix the problem. In one case, I had to recheck the box, restart excel, enter some text into the footer then try to insert the picture and it worked, with the box checked. Then a few days later, it stopped working again. This time, I had to leave the box unchecked. Very confusing & frustrating for the users.

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  3. Anonymous
    2024-03-18T19:51:12+00:00

    https://www.excelforum.com/excel-general/1420093-error-400-when-inserting-a-picture-in-a-comment.html

    I was having the issue and turning the "Connected Experiences" settings off from this post allowed me to add the pictures to the comments.

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  4. Anonymous
    2024-01-31T10:19:23+00:00

    Hi Matthew,

    I'm having the same issue.

    Did you finally get a solution?

    Thanks a lot!

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