On Error

Error handling in VBScript is very basic, there is no option to immediately branch to an error handling routine.
VBScript does not support GoTo or labels that would allow a program jump.

When error handling is enabled, execution will continue onto the next line. To trap an error you have to explicitly test the err object to see if it holds an error.

Syntax 
      On Error resume next    - Enable error handling

      On Error goto 0         - Disable error handling

Error properties:

   err.Number (default)
   err.Source
   err.Description

Examples

In the examples below - replace the 'code goes here' line with your VBScript commands.

Example 1) Trap an error

On Error Resume Next

' code goes here

If Err.Number <> 0 Then
    'error handling:
    WScript.Echo Err.Number & " Srce: " & Err.Source & " Desc: " &  Err.Description
    Err.Clear
End If

Example 2) Trap an error or success

On Error Resume Next

' code goes here

If Err.Number = 0 Then
    WScript.Echo "It worked!"
Else
    WScript.Echo "Error:"
    WScript.Echo Err.Number & " Srce: " & Err.Source & " Desc: " &  Err.Description
    Err.Clear
End If

Example 3) Trap an error

On Error Resume Next

' code goes here

If Err.Number <> 0 Then ShowError("It failed")


Sub ShowError(strMessage)
    WScript.Echo strMessage
    WScript.Echo Err.Number & " Srce: " & Err.Source & " Desc: " &  Err.Description
    Err.Clear
End Sub

“Success is falling nine times and getting up ten” ~ Jon Bon Jovi

Related VBScript commands

Syntax - error codes
InputBox - Prompt for user input.
Equivalent in PowerShell: ErrorAction and $errorActionPreference