Hello NISH,
Have you scanned your system for malware (spyware, adware, trojans, and
other pests) using other tools, like Ad-Aware, Spybot S&D, a-Squared, Ewido,
Spyware Doctor, Pest Patrol (online)?
I did google it, and it doesn't look good,
http://fileinfo.prevx.com/adware/qqd24560798391-SYSL30032621/SYSLEM.EXE.html
http://www.greatis.com/appdata/d/s/syslem.exe_Removal.htm
Good luck
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