|You shouldn't just disable the warning. That's kind of like covering up the "service engine" light on your car's dashboard. Sure, it will hide the error message, but eventually the underlying problem will resurface. As pointed out in suatcini's second link, the underlying problem could cause you to "...lose data, possibly everything, on the hard drive if you run out of space on it." Definitely pay attention to this warning. Don't just suppress it.|
In this case, the underlying problem is - gasp! - your drive is full or nearly full. That's the problem you need to fix. Here's some - gasp! - useful suggestions for dealing with that.
1. Delete unnecessary files using Vista's built-in Disk Cleanup utility.
2. Use Spacemonger to find folders or files that take up too much space
3. Possbily free up many gigabytes of disk space by installing Vista SP2
How to ask a question.