My first guess is that the culprit is a stuck key on the computer keyboard.

Could be electronicallly stuck, or physically stuck.

Articulation Tool.

Check the metatool trigger key for the upbow articulation. What letter key on the computer keyboard?

Expression Tool.

Check the metatool trigger key for the sfz expression. What letter key on the computer keyboard?

Smart Shape Tool.

Check the metatool trigger key for the wrong smart shape. What letter key on the computer keyboard?

Thanks Peter,

I checked, but in a new document the trigger keys for sfz, the upstroke sign are different. I updated my post with more info about my setup.

… When these problems occur, they also occur when I open a new document. So I guess it doesn't have to do with my files …

… I checked, but in a new document the trigger keys for sfz, the upstroke sign are different …

Yes, the metatools are document specific.

The stuck key will trigger whatever metatool is assigned to it, in the currently open document.

I guess I was not clear.

My questions were meant as a test (not a solution), to find out what key is stuck.

… Sometimes I select a note, even in a new document and I have the articulation tool selected, and it gives me this upstroke articulation (or upbow for violin) instead of letting me select an articulation …

To find out what key is stuck, open the Finale document that behaves as you describe (= in the Articulation Tool giving you the upbow symbol instead letting you select an articulation).

Articulation Tool.

Check the metatool trigger key for the upbow articulation. What letter key on the computer keyboard?

That key is probably the stuck key.

Thanks. I will remove this post, because it might be an interaction problem with another program which is running in the background, called 'hold key'.

Don’t remove your posts. It I highly unlikely your situation is unique. Leaving such threads up helps others.

Please verify that what you suspect is the real problem and report back. You can edit your original post and change the title since this is apparently not a Finale bug.