The Quota Exceeded error pops up and also makes an audible sound to alert you that you have exceeded your local storage quota. This is the space that is allotted to your browser for it to save files onto your local hard drive. The allotment should equal about 10% of the free space left on your hard drive. The recommended minimum requirement of free disk space before doing a recording is 20GB. This should ensure that you have 2GB free to save the audio backup.
If this error is shown, you should stop your recording and clear off more space on your hard drive before recording again. If you ignore this error and your Dropbox upload fails, you could risk losing the audio for good since there was no space available to save the backup.
Alternatively, you can delete past Zencastr recordings that were backed up. You should only do this if you are confident that all past recordings are safely uploaded to your Dropbox account.
To delete your past backups in Chrome:
Paste this link into the URL bar chrome://settings/content
Under Cookies, click on 'All cookies and site data'
Scroll down to the entry for Zencastr or search for Zencastr in the top right corner
Click on Zencastr.com
Click on the button that says Indexed Database
Click the Remove button
To delete your backups in Firefox:
Paste this link into the URL bar about:preferences#privacy
Under Cookies and Site Data, click on Manage Data
Search for "zencastr" and then click Remove All