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This is often caused by a browser cache issue but is sometimes a sign of incompatible hardware or software. Please refer to the system requirements on ProctorU’s website (scroll down), then follow the steps below in order.
Check your operating system version (How to check your operating system version: Windows & Mac). Update if possible.
Verify that you’re using the latest version of either Google Chrome or Mozilla Firefox (how to update Chrome, Firefox). Update if necessary.
Clear your browser cache and cookies (How to clear cache and cookies: Chrome, Firefox).
Restart your computer.
If the problem persists, try switching to another browser (e.g. try using Firefox if you’re running into problems in Chrome, and vice versa).
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