Install of Metrics Designer 10.2.1 won't open files

[scott_cmpa]

I have an installation of Metrics Designer 10.2.1 that will not open any scorecard models.  Each attempt to open a file generates the error:

PD-MD-0033 CM-REQ-4154 This request is not valid because it was incorrectly signed.  The security keys on the computer running Content Manager may not match the security keys on the computer that originated the request.  CAF-WRN-2082 An error has occured.  Plase contact your administrator.  The complete error has been logged by CAF with SecureErrorID:...

However, this is only for one machine.  Another machine with the same installation opens the same files without any problem.

We have attempted to drop and recreate the csk and encryptkeypair and signkeypair folders, and have also reinstalled Metrics designer.

[SomeClown]

On rare occasions, I've also had to delete caSerial

On the reinstall, did you delete install folder, reboot, then start install?  Going over the top of an existing install directory would not clear a key problem.