Thanks for the help.
It is NTFS.
The browsable check box not checked in System --> Setup --> QVS@sever==> (right side) Folders -->Mounted Folders --> User Documents. Once checked, I can see the documents. But there are 6 documents in the User Documents folder but I can see only 3. Please let me know how to resolve. I am using my NT user id to login, I am part of Qlikview Administrator Group.