The following function returns an error string for any valid error number:
Function ErrorString(lngError As Long) As String
    Const conAppError = "Application-defined or "
        & "object-defined error"
    On Error Resume Next
    Err.Raise lngError
    If Err.Description = conAppError Then
        ErrorString = AccessError(lngError)
    ElseIf Err.Description = "" Then
        MsgBox "No error string associated with this number."
    Else
        ErrorString = Err.Description
    End If
End Function