Why does a warning message appear on Windows XP?

Warning Msg:
The free disk space of the drive is getting scarce.
To free the drive space by deleting old or unnecessary files, click "here".

The warning message appears when the free space of the hard disk drive becomes low.
Clicking "here" in the message starts Disk Cleanup Wizard.

The frequency of the message display varies, depending on the amount of free space of the hard disk drive.
- When the free disk space becomes 200MB or lower;
The message appears for 10 seconds per session.

- When the free disk space becomes 80MB or lower;
The message appears for 30 seconds, twice per session and once in 4 hours.

- When the free disk space becomes 50MB or lower
The message appears for 30 seconds and once in 5 minutes until the free space exceeds 50MB.

For more details, please refer to the following solution in Microsoft's technical support website.
Article ID: Q285107
Last Reviewed: October 18, 2001
Title: Description of the Low Disk Space Notification in Windows XP