You see the ads for them all day long on TV. Ominous warnings about how slow your computer is running and how much faster it can be. Promises of fixing problems and removing errors. So what exactly is the truth behind these programs?
The simple answer is in over 20 years of working on PCs I have never seen a problem that can be resolved by running one of these programs. In fact the opposite is true. I fix several computers a month that have been damaged by these programs.
These programs use scare tactics and over reporting to make you think they are doing more than they really are. Harmless mistakes in the registry are reported as major errors that require attention. The truth is these ”errors” would never cause a problem and “fixing” them will not improve performance.
Some people seem to develop an addiction to these programs running 5-6 of them all on the same system. The only thing this accomplishes is slowing down the PC, often to the point of being unusable.
My advice is never run these programs. If you computer is running slow or crashing take it to a trained professional. If you are experiencing blue screens it is a sign of very severe problems and no program in the world is going to automatically fix the problem for you.