Just click the GTA VC's folder when navigating and then press connect. Hope you get lucky

If not, I'd go for reinstalling both GTA VC and VCMP to different location (aka if it was in C:\Program Files\Rockstar Games\Grand Theft Auto\Vice City
Install it to C:\Program Files\GTAVC. If that doesn't work, well, throw ur PC out of the window, buy new one, install GTA VC and VCMP to fresh Windows and win

Goodluck getting back in game ^.^