Unexpected #Name error (XP)

[dmitri]

I'm getting a very strange error. I have an .XLL file with a number of functions in it. I have one particular spreadsheet I'm working with where some of the functions from that XLL work just fine and some produce a #Name error. The formulas that produce the #Name error show up in the Function WIzard and, the weirdest part of it, work just fine in other spreadsheets. I can't figure out what makes this spreadsheet different.
The function that doesn't work is pretty simple. It takes two strings as parameters and returns a double.
One more note, all functions in this XLL used to reside in an XLA and have been moved to an XLL for speed. The spreadsheet that doesn't work used to work with an XLA and has been repointed completely to the XLL. All XLA's have been removed from the system and there are no path names in formulas.
I'm completely lost here. I wonder if anyone has any ideas.

[WebGenii]

I can not answer your question, but I do have one of my own. What does an XLL do?

[dmitri]

An XLL is essentially a DLL where you can write formulas in C accessible from XL. Those formulas can be setup to show up in function wizard just like any other formula. Writing them in C makes them significantly faster than the ones written in VBA.

[pieterse]

Would it help to reference the xll in the workbook in question (VBE, Tools, References)?

[dmitri]

No, that doesn't work. We were able to find a workaround by creating a differen alias for the same function in the xll and that worked. It's still pretty weird.

[LegareColeman]

Could you possibly be using XL reserved words for those names?

[dmitri]

Not unless DBXLInstrumentPosition is a reserved name.