@Paxton
Does "FILTER" mean this Filter function?
Does the array or range to filter is the result of TRANSPOSE function?
Any error message please share with us, or you may take a screenshot.
Please test this Filter function on a new workbook.
I do the test on Excel, Version 2012 Build 13530.20376 for Filter button and filter formula, this issue does not be reproduced.
If this issue just occurs with your specific workbook, please check whether the sheets are grouped.
I also suggest you right-click each sheet name > Move or Copy > creat a copy, then update the defined names and TRANSPOSE function, then test this issue.
If this issue occurs with all workbooks, please perform a Online Repair for Office from Control Panel.
Any updates please let me know.
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