One can find legal keylogger systems that are often installed by companies for productivity purposes. The malicious ones are often installed as a hidden part of software and attachable files may contain them too. The first step on how to remove a keylogger is to make use of security software. You should make sure that you have security software installed. This type of software is also freely available on the internet. The first thing is to do a security scan and if the software detects a problem, it will generally quarantine it. There are other ways you can try. If you do not feel confident about trying this yourself, get assistance from someone you trust.
You have to turn off the system restore option on your computer. Go to start/control panel/system/system restore and put a checkmark against 'turn off system restore on all drives.' Then 'apply.' This removes all restore points, but if there is a threat, the chances of being infected again are minimized. Now restart in safe mode. Press F8 while the computer is restarting and this will eventually offer you a safe mode option. Do a system scan again. Once you are satisfied that you have rid your computer of the spyware, re-activate 'system restore' again.
Another option on removing keylogger is to do a 'system restore' to a time before the infection. This, however, can of course only be done if you know more or less when your system became infected. I personally managed to clean up my PC with a powerful spyware and keylogger cleaning software which you can find at Webroot Antivirus
