New Bug Encountered: HTTP Error 400. The size of the request headers is too long

I have an app that whenever changes are synced, the sync fails and the following error is displayed at the top of the page. " Bad Request - Request Too Long - HTTP Error 400. The size of the request headers is too long"

Any ideas?

@JoeBirk Are you still seeing this behavior? If yes, would you please send an email to for investigating. Please add your app details like:
#1 - Account ID
#2 - App name
#3 - Timestamp when this happened
#4 - Where did you see this error? With the browser or mobile device?


I will send a mail to

Feel will my problem is related.

For me, it happens when I push the limit of making a multi-criteria search through a filtered virtual column with a quick edit for having a realtime result and exporting in CSV with an action.

OR( ISNOTBLANK([_THISROW].[Status]) , IN([Status] ,[_THISROW].[Status]) ),
OR( ISBLANK([_THISROW].[Status]) , CONTAINS([Name] ,[_THISROW].[Name]) ),
OR( ISBLANK([_THISROW].[DateStart]) , [Date] >= [_THISROW].[DateStart] ),
OR( ISBLANK([_THISROW].[DateEnd]) , [Date] <= [_THISROW].[DateEnd] )

This obviously generates a back-end request mad long !!!

Maybe using a filtered slice will make the request shorter


I just test,

Using Slice to perform the search criteria and exporting the result work. [ i was sure ]

But we lose some of the capabilities :

Real Time :

since the search slice is only updated by the backend a sync is needed to send back the resulted slice [not really a problem]

Easy multi-users search at the same time :

since the show search result isn’t made on the device with a related row a user search management must be implemented.

    Search criteria table with a security filter [Employee]=USEREMAIL() [ProPlan]

Quite easy to do,

So its solved, just if an AppSheet creator want to add this feature he needs to go to a Pro Plan

I wasn’t really in a need for my apps, I just like to test things around and reach limits
Now i know i can make it, and/or pupose to client

Nice day to you and the team,