Apologies if this has already been asked but I searched a few times and couldn't see a similar question.
I've come to rely on alt key shortcuts in some applications. For example, in Skype alt+1 / alt+2 switches between the 'Contacts' and 'Recent' tab. And in MyLifeOrganized, alt+1 switches views in some way too.
But all these alt+_ key shortcuts have stopped working on my desktop computer. Instead, when I try to use them, it just highlights the menu bar, the same way as I would expect if I just hit Alt by itself. There is no indication that I've used alt in conjunction with another key. These shortcuts still work fine on my laptop, but on my desktop they don't work in any program anymore. Has anyone encountered this and know why it might be?
Edit: To clarify, the problem is not program-specific. ALT shortcuts have stopped working on all programs on my computer, and instead just they highlight the menu bar as if I had pressed ALT by itself.
My keyboard layout is US/UK English (I alternate between them, the same problem occurs with both).