It is part of the windows installer package....this is used to install software on your system and should not be stopped or removed...

If you are having problems in installations of programs then it is probably due to a corrupted installer file from a previous installation...

Try this to resolve this problem:

In control panel > add/remove programs...look for windows installer..xxxxand remove it....then go to windows update and reinstall the program...or search for an alternate sollution of reinstalling the windows installer package.