Installer Quit Unexpectedly

Recently updated to El Capitan. Now I'm getting pop up notices indicating "Installer Quit Unexpectedly." I've looked around and can't find a fix for El Capitan. Only pops up when on the internet (Safari and Firefox). I haven't seen this happen on any other apps.

Any help would be appreciated.

As it only occurs when you have a browser open it may be an online installer of some type. Try disconnecting from the internet, open your browsers one at a time and clear your History and Data. Then restart the computer and reconnect your internet connection and reopen your browsers. It might also be worth downloading and running Malwarebytes Anti-Malware for Mac. https://www.malwarebytes.org/antimalware/mac/ Just in case you have picked up some malware.