Sometimes these quirks can happen when installing a new version of Blender and choosing to load previous version settings on the splash screen.
It may be worth trying a re-install of Blender.
Like Spikey, I think I remember someone with a similar problem. I believe re-installing fixed it, if I remember correctly.
what version of Blender are you using?
The reason I ask is, If you are worried about updating to a new version and opening a file you are working on,
There is no need to worry. If you are using 3.6.2 and update to 3.6.4, for example, there is minimal difference. The last number in the sequence is only an indication of an update for bug fixes, Blender UI and everything else remains unchanged.
