Reboot into Safe Mode (hit F8 key until menu shows up).
Open Hijack This and click on Scan. Check the following entries,
if they are still there.(make sure you do not miss any)
O20 - Winlogon Notify: H323TSP - C:\WINDOWS\system32\irpsl5771.dll
Please remember to close all other windows, including browsers then click Fix checked.
Delete the following Files indicated in
RED and Folders indicated in
BLUE if they still exist.
C:\WINDOWS\system32\
irpsl5771.dll
Reboot into Normal Mode and run new HijackThis scan. If there were some entries that didn't show up in Safe Mode, you may check and fix those that appear now in normal mode (if you do that, make sure to run a new scan again). Save the log file and run
KRC HijackThis Analyzer in the same folder to get the
result.txt log. Just post the contents of the result.txt file in the forum.