Some divisions have had issues with PCR data and pop-up windows. You must NOT block pop-up windows in PCR in order to see and input marks/grades.
To unblock, you must uncheck "block pop-up windows" in the Preferences menu in your Browser.
In Safari, you will find this under the Security tab.
In Firefox, you will find this under Privacy and security
Chrome is configured a bit differently. Go into Preferences, and then you will find this under Advanced in Privacy and Security and then Content Settings sections. Click on the Popups section. Slide the slider from Blocked to Allowed.
Apparently, the programmers have tested PCR in Chrome so that may be the best browser to use if you are having issues. If you continue to have issues see me.