Unresolved External Cla$Hookbutton in NETDL001.OBJ

Help, I messed up my dev environment and tried to recover, but now I get error - where should it be finding this - it is not in builtins.clw

Unresolved External Cla$Hookbutton in NETDL001.OBJ

Sorry - Found the issue - somehow the project link mode got switched to DLL instead of LIB for this EXE