I googled it. Something you could easily have done yourself, by the way.
The first 2 hits (apart from your post):
http://www.prevx.com/filenames/X1051571302143410306-X1/LISER.EXE.html
http://www.virusremovalguru.com/?p=2808
So better find your favorite antivirus or dedicated removal tool and use it.
Kees
I have WinXp Sp3 installed with 2 GB RAM. I found a process named liser.exe in the task manager. What is this process, and is it safe to terminateit as I have never initiated such a process.

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