Excel isn't saving VBA reference

Question

I created an Excel .xlsm file with a bunch of functionality in some VBA Modules/Classes and now I've decided to separate out the code because it will be shared across 4 different sites.

I saved the vba_code.xlsm to a shared location and created my 4 different siteXYZ.xlsm files.

In each siteXYZ.xlsm file I would go to the "Tools | References" menu in the VBA editor and add a reference to the shared vba_code.xlsm at a shared file location \\share_location\\fileLocation\\vba_code.xlsm

At this point, I tested out the functions in siteXYZ.xlsm and everything would work fine.

However, every time I saved siteXYZ.xlsm, closed Excel and then reopened the file it would lose the reference to my vba_code.xlsm file.

How can I keep the VBA references saved with my siteXYZ.xlsm file?

Answer 1

After spending hours searching for an answer and trying various methods such as adding a digital signature to the vba_code.xlsm file and trying to programmatically add the reference on Workbook_open I found a forum post describing the problem:

My siteXYZ.xlsm file had no VBA code or macros defined within it so Excel refused to save the VBA Project and as a result did not save the VBA Reference to vba_code.xlsm.

The solution was simple:

Add ANY VBA code to the siteXYZ.xlsm and save it.

I just double-clicked ThisWorkbook under the VBA editor and added a function to Workbook_open that doesn't do anything:

Private Sub Workbook_open()

End Sub

Answer 2

The usual method of achieveing this is by saving your vba_code.xlsm as an addin (XLA or XLAM) and storing it in the shared location, then adding the addin to Excel in your 4 different sites.
You can also extend this approach by using your own Addin Loader instead of Excel's.
There is a working example of an Addin Loader at http://www.decisionmodels.com/downloads.htm

Answer 3

Following @nvuono

You need to add some kind of module/reference to the excel file for it to save the references you have added.

Private Function addJunkModuleToGetReferencesToSave(ByRef wb As Workbook)

    Set new_module = wb.VBProject.VBComponents.Add(vbext_ct_ClassModule)
    new_module.name = "Junk"
    new_module.CodeModule.AddFromString ""

End Function