[Queen Lizzy]

This Info, Startup disk is full has been poping up on my MacBook Air. I have tried to delete some apps but no help. Today I tried saving excell files and I couldn't. Please what can I do to fix this. I am scared my MacBook may crash.
Elizabeth, Nigeria.

[michelfo]

Short term easy quick fix that might work: restart your Mac. Sometime, the disk will fill with temporary files or virtual memory which get all reset when restarting.

But before you restart, it might be a good idea to open Activity Monitor (in /Applications/Utilities) to check if an app is taking an unreasonably huge amount of memory (in the Memory tab), basically growing and growing in virtual memory and taking up disk space. If you find the culprit, quitting that app (so it can't continuously leak memory) might help. If not, at least try a restart.

Lastly there's the obvious solution: you can delete files and applications from your hard drive to make up space. Seems like you already tried that which is why I suggested checking for an app leaking memory.