How to delete temporary files to free up hard drive space

Question: I am trying desperately to find more hard drive space. I’ve already replaced my hard drive once and the computer is getting too old to warrant spending any more money on it. In my search for anything to erase, I’ve noticed a lot of files with the extension of TMP. One in particular is 19 megabytes, so it would make a huge difference if I could clear it off my hard drive without causing any harm. Can you tell my what this file is for and whether or not I can safely delete it? —R.W.W.

Answer: Windows creates a special directory called TEMP. It sits usually in the c:windows directory. It keeps files with the extension .TMP in there. TMP (short for “temporary”) files are used by a program as a place to put data when it needs a “holding pen”, sometimes during an install or occasionally during normal data operations. Think of it as scrap paper for computers. Also, some programs will dump unsaved data into TMP files when a crash occurs.

If the TEMP directory is not specified or if a program just feels like it, it will put a TMP file in the directory it operates in, or anywhere else for that matter. There seems to be no rhyme, reason, or rules for this. So you’ll end up with a hard drive littered with these useless files.

Typically, you can safely delete .TMP files. Close down everything but Windows first, to make sure you aren’t trying to delete anything a program might be using at the moment.

Before you go blowing the big 19-megabyte file away, you might want to rename it to something else first and see if the system complains about it over the next few days. It’s unlikely that the data giant you’re concerned about is anything important. It’s more likely a leftover from some past install that you aborted or that didn’t clean up after itself. Still, it can’t hurt to be cautious. If you rename it, and your system doesn’t seem to miss it after a few days or normal operation, you can probably go ahead and delete it.

An even safer way to deal with these files is to let a commercial piece of software handle the cleanup for you. Products like Dr. Salman’s Disk Space Recovery Wizard detect unused files or data clutter, and dispose of them for you safely.

If you’re looking for hard drive space, another type of file you might consider removing is the one with .SPL extensions. These files might be found in c:\windows\spoolprinters. These are files created by Windows in preparation for sending data to a printer. Once the document is printed, the .SPL files are no longer needed. Again, if you have any doubt, save copies with different names and see if the system complains. (Of course it would be a bad idea to delete an .SPL file if a print job is in progress!)