In some systems having the following problem
Copy new certificate replacing old one.
- Copy registerCAcft.exe from eMO client folder to all other folders.
- Double click registercacft.exe and click yes.
- Now run communication. Sometimes it won't run.
- If so right click on certificate select install next select second radio button and trusted root certification authorities and next next finish.
Now try again. For DET do the same delete any files in data folder outside txd and also inside txd and run.
The Installation of New certificate is not possible better to change the communication modules in some other PCs.
Thanks to Rajesh C.R
Extracted From potools.blogspot.com