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
    2024-01-26T16:10:25+00:00

    I've already got a support ticket open, thank you for trying!

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  2. 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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  3. Anonymous
    2024-02-02T15:10:48+00:00

    Hi, this worked for me. When inserting a picture it gave me an "error" that said that function needs to be offline, but I can select "work offline" which takes me to the windows explorer pop-up to pick the picture from my computer.

    Not sure of any other issues turning this off will cause, but good solution, thank you.

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  4. Anonymous
    2024-02-25T19:17:52+00:00

    Looks like this solution no longer works. :(

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