Microsoft has fixed a known issue that causes copy-and-paste failures for some Excel users after installing the September 2026 KB5002914 security update. [...]
The installation of the September Patch Tuesday generated many bugs, including a very annoying one that prevents the copy-paste from working. While waiting for a complete fix, Microsoft shared a bypass solution.
An update has paralyzed an important function in Excel. Since then, users can no longer copy and paste content. Up to a fix by Microsoft, there are still some workarounds that can try affected people. read more on t3n.de
After the September update, inserting in multiple Excel versions can fail without an error message. Microsoft investigates the error and now calls an official workaround.