Welcome to LabVIEW Installation 101! I'm guessing that when you "uninstalled" LabVIEW, you did not to go Control Panel, choose NI Software, and click on Remove All, right?
If you did a piece-meal LabVIEW removal, and especially if you deleted files and folders from your hard drive yourself, you have made life very challenging for yourself. There is one safe (and basically guaranteed-to-work) method -- backup all of your data and User files, reformat your hard drive, reinstall your Operating System, reinstall all your other programs, restore your data, and then install LabVIEW. Trust me, I've been there and done that.
Otherwise, you can sometimes get your system to a "clean" state, but it involves the reasonably-dangerous task of removing references to LabVIEW, NI, and a few NI-specific things (I don't have specific examples) from the Windows Registry. Mucking with the Registry can force you to do a Windows re-install, so if you are in doubt, take the safe (and, in many cases, faster) option of a Complete Reinstall.
If you do manage to get your registry clean, you can consider deleting the existing NI Files and Folders. However, as you've learned, doing this yourself can cause problems. If you are going to re-install, the new files should overwrite the old ones (unless you are uninstalling less than you had previously).
Bob Schor
