A common module must have at least one export method and region "Public" or "Internal".
Incorrect
// Start module
Procedure Test(A)
A = A + 1;
EndProcedure
// End module
Correct
// Start module
#Region Internal
Procedure Test(A) Export
A = A + 1;
EndProcedure
#EndRegion
// End module
Source: Standard: Module structure (RU)