Dev dll erroring with 'Class does not support automation'

[earme]

I have dll's that I use in my asp pages, some dll's call other dll's in addition to being called from the web pages. All dll's have a Dev Version and a Prod version (they have Dev or Prod at the beginning to signify which one they are). The dev and prod versions use the same cls files, but have different project files. Up till now this process has worked wonderfully.
Using the Prod dll's everything works fine, but when I use the Dev dll's on the same site, one of my dll's consistently fails with the error 'Class does not support automation or does not support expected interface.'
I've compared the project setting of this dll with it's prod one and with other dev dll's, but there doesn't seem to be a difference. I've rebuilt it multiple times, but to no avail.

Any ideas?!
Thank you!
Earme

 

[LazyMe]

And did you check if the required method is actually available for clients (with for instance VB object browser, or OLE view)?
Greetings,
Rick

 

[earme]

The Prod dll works fine on the development machine. It uses the same code and appears to be set up exactly the same as the Dev dll. When I use the Dev dll, on the same development machine, it errors. They appear to be set up exactly the same and use the same cls file. So, the calls that the Dev dll is making and erroring on, works fine for the Prod dll (on the same machine).
In my asp code I have a global variable set that tells the asp project which mode (Dev or Prod) to run in, and from there it knows which dll to get. So, to switch between the two I change the global variable, restart iis and test the site. I've never had a problem with the dev dll not working the exact same way as the prod dll before.

Thanks,
Evie

 

[Spellman]

Does the development DLL reference other development DLL's which aren't on the machine as opposed to the production DLL referencing other production DLL's which are. Sorry if thats a stupid question but just to eliminate all the obvious. Mark

The key to immortality is to make a big impression in this life!!

 

[earme]

I solved the problem. It was a binary compatability problem. I copied the last working dev dll's from the client back to my dev machine and built everything again, making sure that the binary compatablity was with this older, but working, dll. Tested it on the dev sites, and like magic, everything is working again.

Evie