I have purchased Trend Micro Titanium Maximum Security and am now unable to install any plugins. I have had these plugins before and had no trouble with them but now they have disappeared. I tried closing the antivirus and added mozilla.org to the exceptions list but it did not help. I have copied the text of the error. Firefox could not install the file at https://addons.mozilla.org/firefox/downloads/latest/3006/addon-3006-latest.xpi?src=search because: Unexpected installation error Review the Error Console log for more details. -203