Could anyone help me solve a very stressfull problem!

I have an MTS ActiveX dll written in VB and when I try to access a method of the dll I keep getting Run Time error 70. I have tried all of microsofts suggestions with regards to running DCOMCNFG and playing around with security etc. I have also played around with MTS permissions and still have not had any joy. This problem is a strange one as there is a pc in the office with all the same environment and dll's which works.

Can anyone help me?