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
    2024-04-17T19:57:49+00:00

    Hi Josie

    Thank you!

    Indeed that worked however, since then, it keeps asking me to restart Office 365, even though all my MS apps are closed.

    Did you have the same issue too?

    Thank you again

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  2. Anonymous
    2024-04-22T13:53:35+00:00

    I just discovered that in Options...General I have a section called LinkedIn Features, which was turned on. I unchecked the box to disable this, and the Background selection immediately began working. Did not even have to restart Excel.

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  3. Anonymous
    2024-04-25T13:09:59+00:00

    I had the same problem, but it was resolved using an alternative internet network.

    I asked the infrastructure team to check if there is a blockage in the firewall. While they don't solve it, when necessary I use a hotspot for these activities.

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  4. Anonymous
    2024-04-26T11:26:36+00:00

    I had the same issue.

    I tried the following steps:

    1. Diconnect the internet
    2. upload image using work offline

    It worked.

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