SCN files are created whenever you use the TOPSCAN utility program to scan a TOPSPEED file and change the display formatting i.e. columns visible, column picture formats, etc.
TPB files(maybe) be a backup of the TPS file whenever a backup is made by the TPSFIX utility program before rebuilding.
As for the system prompts you have to be more specific as to the exact message being shown & when & in which program before I can try to reply that.