- Click on the Tools menu (the little gear in the upper-right corner) and select "Internet Options"
- A pop-up will come up. Click on the "Advanced" tab at the end.
- Under the "Browsing" category, uncheck "Enable third-party browser extensions".
- Restart your browser and try the entry again.
If the error does not occur, it was caused by a plugin. You may determine which plugin is causing the error by re-enabling the plugins and disabling them one by one in Tools -> Manage Add-ons. When the problem occurs again, you will have found the offending plugin.