Windows Mobile 2005 security model FAQ
Q: Why doesn't the device trust my code? I bought a code signing cerificate from a CA!
A: Because the certificate doesn't chain to an execution root on the device. For a binary to be trusted, the cert must chain to a certificate in the Privileged or Unprivileged Execution Authorities stores. A typical Windows codesigning certificate from a CA won't work. Get a Mobile2Market certificate to run on the widest variety of devices.
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