I use windows 7
after uninstalling it i see entire F drive of my hard disk is blank. All data loss.
This is not related to MultiBit.
Are you sure? it sounds like the uninstaller deleted more than it should have.
I suppose the deletion operation, even if deleting the correct files, may have caused the drive to fail.
If you care about the data you lost, dont use free software. Hire someone. Data forensics software can be really bad and destroy your data entirely.
Should not be a problem if they work on a
copy of the disk image.