I have a client that cannot open one of our models.
Sounds like the file is crashing right off opening. He is
getting a comple error that says "cannot find project or
library" This client has run these type of spreadsheets
before. He is using Excel 2003. We are using Excel
2000. The model opens up properly on my machine.

In Excel the client has his add-ins installed.
Analysis Toolpack
Analysis Toolpack VBA

In VBA his tools/references have:
Visual Basic for Applications
Microsoft Excel 11.0 Library
OLE Microsoft Office 11.0 LibraryAutomation
Microsoft Forms 2.0 Object Library

The only difference that I can see if that we are using
the 9.0 library for Excel and Office.

Why would a later version of Excel not run this file?