Help!.....Def!.....Or, anyone else out there who knows how to handle this: I tried to launch my standalone (windows) TWS, and nothing happened. No login window, no anything. I clicked on the icon and got the "hourglass" for a few seconds, then nothing. After trying several standard "fixes", I concluded that part of the software had possibly become corrupted during some recent hard drive problems that I had experienced. I decided to uninstall TWS, and then reinstall a fresh copy/version. When I try to install the new copy, I continue to get the "Fatal Error" message that the setup process has detected an existing version of TWS on my computer, thus ending the new installation. When I uninstalled, I went into the "add/remove program" function via control panel. Subsequently, I used Windows Explorer to delete the remaining directories/folders that I thought were associated with TWS. How do I do a COMPLETE uninstall, such that the setup function will allow me to reinstall?
If IB forum doesn't help, you could trying installing JV16 or RegCleaner from http://www.vtoy.fi/jv16/shtml/software.shtml then use the registry cleanup option to delete all old/useless registry keys. Then use the "software" page to identify parts of TWS program that still exists on your drive, then manually delete them all.
I fixed it. Opened the Registry Editor and deleted all references to IB and or TWC. Then reinstalled with no problem. Thanks to those who responded.