Hey Brandon,
As Robert has mentioned here, this could be an update issue. This is why I was curious what version you were using. If you are on a later version make sure you run the "check for updates" and are up to date on config files, etc.
I can't be 100% but I think it was the GPS or Office configuration utility that needed updated to resolve that issue when processing data. This could be the same issue for the IGS rapid orbits download as well.
To be save I would just update everything you can in the "Check for updates".
Let me know if that doesn't resolve the issue and what timeframe you are trying to download from if not.
Regards,
Shane Lyons