Proctorio:  “fix error to continue” 
If you are seeing a blank in the red box and clicking on “fix error to continue” does not work. This is caused by the "Disable Extensions" setting, if Proctorio extension is the only one installed in the browser the test taker is unable to "fix errors" and start the quiz:

Check to see if Proctorio is the only extension on your computer by following the steps below.
Three dots in the upper right-hand corner of the browser >> More Tools >> Extensions >> 

If Proctorio is the only extension:

Install one more extension (doesn't matter which one - can be ublock or google sheets or any other). An example of an extension is:  https://chrome.google.com/webstore/detail/save-to-google-drive/gmbmikajjgmnabiglmofipeabaddhgne