this is a documented problem, happened to me too (long time ago)...
check that, u r having Quick Launch Folder in Internet Explorer folder.....
If u do not find Quick Launch Folder there, the path is:-
DriveName:\Windows\Application Data\Microsoft\Internet Explorer\
or
DriveName:\Windows\Profiles\UserName\Application Data\Microsoft\Internet Explorer\
do this...
Go to Start>Run and then type IE4UINIT.EXE and press Enter....this creates the Quick Launch folder, if it is not already there.
if u do have Quick Launch Folder, no need to do the above step, directly do this....
Go to Start>Run and type REGSVR32 /i SHELL32.DLL and press Enter, after this againg type REGSVR32 /i BROWSEUI.DLL and press Enter...
Then Restart.....