We are using Mentor graphics expedition 7.9.5 and DMS 7.9.4 in 32-bit system with OS Windows 7 and the tools are working fine.
With the same installable we are able to install the same in 64-bit system (OS-windows7) as well, but facing issues when launching DMS librarian.
Snap of the error received is shown below.
It would be very helpful if some one can look into this.
Debugging issues like this is very difficult with only the error message to go on. If you have a support contract with Mentor, then I'd suggest opening a service request. I suspect this is out of scope for a resolution on the communities site.