The supplied user buffer is not valid for the requested operation

We use the Desktop Integration on a daily basis and see this message quite frequently.This happens when we connect, or use an office document that has attributes mapped to Windchill, but we cannot replicate it consistently. We are running 10.2 F000, and our system is hosted outside of our network. We also use a proxy server to access the internet.

We have opened a few support tickets with PTC, but we haven't been able to find a solution.

Has anyone seen this error or message? Any thoughts?