With all the latest chatter regarding program errors, Tracing, etc. I decided to write a Macro just for that:

' I #Include it so variables remain consistent across programs  
' If #Including, place #Include line wherever Macros are defined 
   ' for example my Include line is:
' #Include "C:\Power Basic\Includes\Common_Macros.inc" 
 'The variables Chk$ & Check_File_Num& may be initialized Local or Global
 'g_Chk_Print_Flag MUST be Global
 'Destination Folder may need to be reset and/or 
 '       log name changed  
     'typical call: {Change 001 & Using$ to whatever appropriate}
 'chk$ = using$("at 001 x = #   y = #", x, y): m_Check
' Obviously the variable names may be changed to suit your programming
'   conventions. I try to keep them descriptive and short for myself.
Macro m_Check
 Incr g_Chk_Print_Flag 'keeps track to Open or Append the log file
 Check_File_Num = FreeFile
 If g_Chk_Print_Flag = 1 Then 'first time through
    Open "C:\Temp\Track_Log.txt" For Output As #Check_File_Num 
      'You may want to put mor infor in this line
    Print #Check_File_Num, , Date$ & " " & Time$
   Else 'subsequent runs 
    Open "C:\Temp\Track_Log.txt" For Append As #Check_File_Num ' hopefully not a conflict
 End If       
 If Err Then ' in case Error tripped
    chk$ = chk$ & _
           Using$("    Error ### ", Err) & Error$(Err) 
    ErrClear 'Reset for next time called
 End If        
 Print #Check_File_Num, Chk$ & " in " & FuncName$ 
 Close #Check_File_Num 'insures file is written to disk and not cached
  Reset Chk$ 'ready for next time here
End Macro