* I cannot find anything current about this issue on the web. * Quick look does work for "Libre Office" files, although the icon for the file is blank.
* I can no longer preview any PDF files in quick look.
* Preview will open photo files (jpeg, png, etc.) When the Adobe icon is lost it is replaced with a blank sheet of paper with folded corner. Others seem to lose the Adobe icon after I try, unsuccessfully, to open them in Preview. Some but not all files have lost the Adobe icon. * Changed the default app, for all PDF files, back to Preview. The XLab FAQs and read the FAQ on removing software.Last night all my PDF files suddenly appeared with Adobe PDF icon and opened by default, in Adobe reader (latest version). Look for them at VersionTracker or MacUpdate. There are also several shareware utilities that can uninstall applications: Be sure you also delete this item as some programs use it to determine if it's already installed. The item generally has a ".pkg" extension. Usually with the same name as the program or the developer.
Some applications install a receipt in the /Library/Receipts/ folder.
You can modify Spotlight's behavior or use a third-party search utility, Easy Find, instead. Unfortunately Spotlight will not look in certain folders by default. If an application installs any other files the best way to track them down is to do a Finder search using the application name or the developer name as the search term. Look for them in /Library/LaunchAgents/ and /Library/LaunchDaemons/ or in /Home/Library/LaunchAgents/.
Some software use startup daemons or agents that are a new feature of the OS. Locate the item in the list for the application you want to remove and click on the "-" button to delete it from the list.
Open System Preferences, click on the Accounts icon, then click on the LogIn Items tab. Log In Items are set in the Accounts preferences. Startupitems are usually installed in the /Library/StartupItems/ folder and less often in the /Home/Library/StartupItems/ folder. Some applications may install a startupitem or a Log In item. Again, they don't do anything but take up disk space once the application is trashed. You can also delete the folder that's in the Applications Support folder. You can also check there to see if the application has created a folder. Some applications may install components in the /Home/Library/Applications Support/ folder. In some cases the uninstaller may be part of the application's installer, and is invoked by clicking on a Customize button that will appear during the install process. Some applications may install an uninstaller program that can be used to remove the application. If you want you can look for them in the above location and delete them, too. Although they do nothing once you delete the associated application, they do take up some disk space. Applications may create preference files that are stored in the /Home/Library/Preferences/ folder. Most OS X applications are completely self-contained "packages" that can be uninstalled by simply dragging the application to the Trash. Meanwhile why not try uninstalling the product: Contact the developer's tech support to help you.