Some extra notes for a few Posts
http://www.eileenslounge.com/viewtop...278892#p278892
https://www.myonlinetraininghub.com/...andling-in-vba
https://excelfox.com/forum/showthrea...GoRoT-N0Nula-1
https://excelfox.com/forum/showthrea...0559#post10559




On Error GoTo -1 is not equivalent of using Err.Clear. It does ( also) clear the error object, (equivalent of using Err.Clear ).
On Error GoTo -1 takes Excel out of the so called “exception state”. It also does clear the Err object registers, (equivalent of using Err.Clear ). But the later is secondary to its main function of “clearing the exception”.
The next macro has 3 identical erroring code lines . Just before each error we have an error handler, which we might expect would trap the error following it . All three error handlers are similar and are of the type On Error GoTo [LABEL] But we find that only the first two error handlers work….
In this macro the first and the second error handlers, of the type On Error GoTo [LABEL] are enabled, and so when an error occurs the coding jumps to the appropriate Label
The second Error handler would not have worked, that is to say the second error would not have been trapped without the code line of On Error GoTo -1 . On Error GoTo -1 has cleared the exception state.
The third error handler, also of the type On Error GoTo [LABEL], does not work. It does not work, that is to say the error is not trapped , because we are in the exception state. One of the characteristics of the exception state is that any attempt to enable an error handler will be ignored. Another characteristic of the exception state is that any enabled error handler, ( in this case the second one ) , will also be ignored.
It is also sometimes said in this situation that the second error handler is active and is still handling the second error. It cannot handle another error , and any further errors will be handled by the VBA default error handler
Code:
Sub OnErrorGoToMinus1_takes_Excel_out_of_the_so_called_exception_state() ' It also  does clear the Err object registers, (equivalent of using Err.Clear ). But the later is secondary to its main function of "clearing the exception"
Dim Rslt As Double
 
 On Error GoTo ErrHndlr1
 Let Rslt = 1 / 0   ' This error gets trapped by  ErrHndlr1
 MsgBox Prompt:="You will never see this", Title:="You will never see this"
Exit Sub   '   You will never come here in this demo macro, but its good practice to get in the habit of always doing this exit sub

ErrHndlr1:
Debug.Print Err.Number & vbCr & vbLf & Err.Description ' 11  Division durch Null
 On Error GoTo -1      ' the next line will give us no error infomation because the  On Error GoTo -1  has cleared the  Err  object registers
Debug.Print Err.Number & vbCr & vbLf & Err.Description '  0
 
 On Error GoTo ErrHndlr2 ' the main function of  On Error GoTo -1  is to "clear the exception" which means  this second error hanhler will work
 Let Rslt = 1 / 0   ' This error gets trapped by  ErrHndlr2
 MsgBox Prompt:="You will never see this", Title:="You will never see this"
Exit Sub   '   You will never come here in this demo macro, but its good practice to get in the habit of always doing this exit sub
 
ErrHndlr2:
Debug.Print Err.Number & vbCr & vbLf & Err.Description ' 11  Division durch Null
  ' I will not do  On Error GoTo -1  and see what happens...
  
 On Error GoTo ErrHndlr3
 Let Rslt = 1 / 0 ' This will be handled by the VBA default error handler: The error will not be trapped by the second error handler ,  ErrHndlr2
 MsgBox Prompt:="You will never see this", Title:="You will never see this"
Exit Sub   '   You will never come here in this demo macro, but its good practice to get in the habit of always doing this exit sub

ErrHndlr3:
' You will never come here.  The third error is not trapped: It will be handled by the VBA default error handler

End Sub
The following other error things also , in addition to their main function, clear the Err object registers –
_ On Error GoTo 0 ,
_ changing the error handler
_ Resume, ( Resume; Resume Next; Resume [label] )
-.....see next post