"Vlad" wrote

I read here that Excel add-ins don't provide much
protection/security (passwords can be easily broken),
that the way to go is with an Excel COM add-in instead,
and that VB6 is the best tool for designing an Excel
COM add-in.

Depends on language preference. AFAIK there are decompilers for VB6 as well.
C++ will be hardest to break.

However, I can't find a place to buy VB6 anymore.

Check eBay for a used copy.

Can I use Visual Basic.NET Standard instead?

You can, but it provides less protection than VB and add-ins can't be run
without the .NET framework. On the other hand, there are a lot of good
reasons that nobody is buying VB6 anymore ;-)

Jens.

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