I am using a piece of code in ThisWorkbook module to enable outlining on selected password protected sheets. I'm confident that the code does what it's supposed to when it's within a Workbook_Open sub but I am encountering other difficulties. If I save the Excel workbook with a different name, or take a copy of it, when I open the differently titled file, I get the following error and Excel ultimately crashes:

"Sorry, we couldn't find [original filepath\filename]. Is it possible it was moved, renamed or deleted?"

If I use Auto_Open instead of Workbook_Open I don't get this error but I am finding other difficulties with Auto_Open and think that Workbook_Open should be the right sub to use.

There are no links in the Excel file and also no reference to the filename in any of the VBA code. The error/crashing occurs whether the file is saved on a network drive or a desktop and also occurs on other users' computers, not just my own.

I've searched lots of forums and haven't found any reports of the same issue, any suggestions gratefully received.