Some computer maintenance is essential, but too much computer maintenance will probably just waste your time. Separating the essential maintenance from the inessential can be difficult if you don’t quite understand how computers work—and how they fail. Here are five computer maintenance tasks you don’t need to do often and why they’re non-essential.

Computer Maintenance Time Waster #1—Regular Registry Cleaning

The Windows Registry is a database of configuration settings for Windows and for many programs. When something happens on your computer to make the configuration settings differ from the actual configuration, your computer could behave incorrectly.

For example, one of the settings in the Windows Registry tells Windows what programs to start when the computer boots up or when you log into your desktop. If that program gets removed, but the registry doesn’t get updated, Windows will boot slower than necessary because it will look for that program every time you boot up your computer.

Using a tool to “clean” or “repair” your Windows Registry can speed up your computer and fix annoying errors, but you only need to run the registry repair software when you notice your computer getting slow or you start to see odd errors. There’s no real reason to run registry repair software every day or every week or even every month unless you make a lot of registry changes to your computer on a regular basis, such as adding and removing programs.

Computer Maintenance Time Waster #2—Defragmenting Solid State Drives

Solid State Drives (SSD) and hybrid drives are becoming quite popular for the way they speed up disk drive data storage and retrieval. But they seem to suffer from the same problem other disk drives have on Windows—if you use them long enough, data on them gets fragmented (split into pieces).

When a file gets split into two fragments, your computer has to get both fragments from the disk drive and then recombine them. On a magnetic hard drive with moving parts, this requires a small amount of time for the data reading sensor to move from the first fragment to the second fragment. If a file has lots of fragments—some can have over a hundred—it can take a significant amount of time to read the entire file.

Solid State Drives don’t have this problem. Or, rather, they almost don’t have this problem. An SSD has no mechanical moving parts, so (in theory) it takes the exact same amount of time read a fragmented file as a non-fragmented file. In reality, the way the computer has to address small fragments mean there is a tiny bit of extra work, but the slow down is only measurable in nanoseconds.

That means there is no point in defragmenting Solid State Drives. In fact, defragmenting a SSD can reduce its lifetime slightly (the same applies to hybrid drives) because SSDs only have a limited number of write cycles.

Computer Maintenance Time Waster #3—Emptying The Recycle Bin

Most modern operating system file managers (such as Windows Explorer and Apple Finder) automatically move deleted files to the Recycle Bin. This gives you a chance to recover the file before it gets deleted permanently.

Some people empty the recycle bin on regular basis in an attempt to keep their hard drive clean. But emptying the recycle bin when you don’t actually need to negates its usefulness as a file recovery tool. I recommend that you only empty the recycle bin when you need extra disk space. That way you give yourself the best chance to find and recover a file you didn’t realize you still needed before it gets permanently deleted.

Computer Maintenance Time Waster #4—Water Bath

Computer maintenance fanatics will occasionally give their computers a bath. I’m not kidding. A distilled water bath is a legitimate way to seriously clean a computer—computer repair shops do it all the time—but it isn’t something you need to do on a regular basis. For regular cleaning, use a can of compressed air to clear the dust out from inside your computer once or twice a year.

Computer Maintenance Time Wasters #5—Manual Anti-Virus Scanning

There are legitimate reasons to manually run your anti-virus scanner. If you think you have a virus or you just downloaded a file and you want to check its safety, running a scan makes sense. But running your scanner when nothing else has changed on your computer only makes sense if you don’t leave your anti-virus software running all of the time. After all, what’s the point of anti-virus software if you aren’t going to use it all of the time? Preventing viruses from getting on your computer in the first place is some of the best computer maintenance you can do.