Low Disk Space Warning

Low Disk Space Warning: Ignore, Disable, or Obey?

One of the most annoying aspects of Windows is those warning messages that seem to pop up at the most inconvenient times. Although they are designed to warn you when potentially dangerous circumstances arise, some of these warnings are benign and can be closed without taking any actions. And there's the problem... as a result of so many warning messages, and due to a general fear of ANYTHING that pops up on the screen, some users tend to ignore ALL of them. And that can be bad. Sometimes.

One specific warning that computer users will see on a fairly regular basis as their hard drive fills up is the Low Disk Space warning: "You are running out of disk space on Local Disk [drive]. To free space on this drive by deleting old or unnecessary files, click here." So is this one important? Can you ignore it, disable it, or will doing so put your computer at risk?

What is the "Low Disk Space Warning"?

Windows created the low disk space warning to alert computer users when their hard drive is running low on available disk space. The first warning appears when a drive has less than 200 MB of available disk space, the second warning appears when the drive has less than 80 MB of available disk space and the most urgent warning appears when the drive has less than 50 MB of available disk space. As your disk space decreases, the frequency that the low disk space warnings pop-up on your screen increases, and it is because of this that many people decide to disable this warning in their Windows system settings.

Should you ignore these warnings and plow ahead? Here's the test: If you are running out of space on the system drive (almost always the C: drive), then you need to take action right away, or your system performance will begin to suffer, and your ability to recover from problems related to spyware and viruses will be negatively affected. You might even experience a computer lockup or crash (and potential loss of data) if you take no action.

If the warning refers to some other disk drive, such as the D: or E: drive, then probably you can safely ignore this warning. You still might want to explore those drives to clean up unwanted files or programs, but it won't cause any serious problems, expect perhaps that you'll run out of space to store new files on that drive. If you have a secondary hard drive with less than 200MB of storage, and you understand that's not a problem, then you CAN ignore or even disable this Low Disk Space warning. See below for some tips on how to do that.

What Happens When You Have Low Disk Space?

While it may be tempting to ignore or disable your Windows low disk space warning, it is NOT advisable when the problem is on the C: drive. In order for your computer system to operate properly it needs a minimum amount of available disk space on the system drive. The 200 MB threshold is the line that Windows has drawn for optimal performance. Once you fall below this threshold your system automatically takes actions to maintain minimum performance capabilities.

When your available disk space falls under 80 MB, Windows delivers a stronger warning message, and then it starts to free up drive space by deleting previous System Restore points. This reduces the number of restore points you can select from to restore your computer if the hard drive is impaired or corrupted. (See System Restore for more information on why you don't want that to happen.)

The final phase of self preservation comes when your drive falls under 50 MB of available disk space. When this occurs an urgent warning message is delivered every four minutes, until the user takes actions to free up disk space. If you ignore this warning, then Windows will purge the ALL System Restore points, and suspend the System Restore function. System Restore will not be reactivated until 200MB of disk space becomes available on the system drive.

Here's another potential risk of running too low on hard drive space. When your Windows system runs out of physical RAM memory, it will try to create virtual memory by using a chunk of hard drive space. If there is not enough hard drive space available, your applications may fail, you may not be able to open large files, or your system may just fall down and go boom.

Fortunately it's not hard to get your system back on track. You can run the Disk Cleanup function by clicking on the Low Disk Space popup, or you can go to My Computer, right-click on the hard drive icon, select Properties, and then click the Disk Cleanup button. This tool will scan your drives and look for files that you can safely erase. Usually this will include files in your recycle bin, temporary internet files and file fragments. If this doesn't free up enough space then you can consider removing programs that you don't use and moving large media files (videos, music, graphics) to a CD, DVD or jump drive. (See Clean Hard Drive for more help with removing old files from your hard drive.)

Disable the Low Disk Space Warning

As I mentioned earlier, if you have multiple drives, and the problem is not the system (C:) drive, the low space warning is not so important. You can disable the Low Disk Space warning by changing a setting in your system registry. The easiest and safest way to do so is with the TweakUI tool. After downloading and starting TweakUI, click on Taskbar and Start Menu, then UNCHECK the box next to "Warn when low on disk space". Click OK to exit from TweakUI, then restart your system to activate the new setting.

If you are comfortable mucking around in the Windows Registry, then you can make this change without TweakUI. Start the REGEDIT program, then follow these steps:

• Navigate down to HKEY_CURRENT_USER / Software / Microsoft / Windows / CurrentVersion / Policies / Explorer
• If the NoLowDiskSpaceChecks key is not there, right-click to create a new DWORD value with that name.
• Double-click on NoLowDiskSpaceChecks, enter 1 for the value
• Press OK and exit from REGEDIT

Just remember, it's NOT a good idea to turn off the Low Disk Space warning when the problem is on the system drive. Bad Things will happen. Do you have comments or questions about the Low Disk Space warning message? Post your thoughts below...