When you run a VBA routine, a compiler error occurs: "Can't find project or library":
If you confirm the error message with OK, the VBA Editor function not found will be displayed. In this specific case, the RTrim function was called and is unknown, although this is a function with standard functionality.
The same VBA routine has worked fine for a long time, but has suddenly stopped working.
The message for the missing library could indicate a missing reference. It can be located in the VBA Editor under Tool > References to display the selected references:
In the list of selected references is one marked "MISSING". The file name of the library containing the name is OFFICE11, so it is a reference to Office 2003.
This version of Office 2003 has been replaced by a newer version, so the library is no longer available.
The VBA routine will then be able to be started without any problems.