Whenever you upgrade OS X, you always chance an application or two not working with the new software changes. Hopefully problems are kept at a minimum, or are insignificant enough to not require any attention; however, there may be times when apps crash, hang, or show other odd behavior that directly impedes your ability to use them. In these cases, there are several general approaches you can do to fix the problem, before having to dive into specifics troubleshooting steps.

Check for compatibility

First be sure your apps are compatible with your version of OS X. For the most part apps will run on multiple versions of OS X; however, be sure to check with the developer for specific compatibility with the version of OS X you have just installed. Granted its best to do this before upgrading, but doing so after the fact can be done as well.

App compatibility is more than what the developer claims, so even if the app should technically work, bugs may have gone unnoticed. Therefore its good to check with support forums and other online communities for user experiences to see if there are outstanding problems with the app.

Do keep in mind that support forums are inherently biased (after all they are where folks go when things aren’t working, and problems always occur), but you can assess the occurrences of specific complaints to get a better idea of whether a problem may be present.

Install any updates for the app

To ensure compatibility with OS changes, developers generally release updates for apps around the same time as Apple releases OS X updates. Therefore, be sure to check for and install any updates for your app, and then try running it again.

Reinstall the app

Often the most thorough way of fixing app problems is to simply re-install it. OS X updates may remove components of applications that are deemed to be incompatible, or otherwise move items around and result in a broken application. In these cases, reinstalling should overwrite and restore all components required for the app to run properly. However, do be sure to immediately update the app to the latest version before running it.

Clear temporary items from your user account

Apps and OS X use multiple locations to store settings and temporary items that are used to run applications. These can be caches, preferences, or saved window states, but all have the potential to affect an app, and cause problems if misconfigured.

1. Boot to Safe Mode to see if the app runs successfully.
2. Start the app and then immediately hold the Shift key to clear prior window configurations.
3. Hold the Option key and choose Library from the Go menu in the Finder. Then open the Preferences folder and remove files named similar to com.COMPANY.APPNAME.plist (where COMPANY and APPNAME reflect the app’s developer and title). Examples would be “com.apple.textedit.plist” for Apple’s TextEdit program, or “com.adobe.illustrator.plist” for Adobe Illustrator.
4. In the same Library folder, open the Containers directory and remove folders within it that follow the same “com.COMPANY.APPNAME” naming scheme.
5. Again in the same Library folder, open the Caches directory and remove files and folders that follow the same naming scheme, though there may be others in this folder that are just named after the developer or the app.
6. Go to the Application Support folder in the Library, and move any folder within it to the desktop that is named similar to the application or developer. These folders may contain user data (file templates, and configurations) that you might want to preserve, and if the app fails to run, then move these folders back.
7. Open the Terminal (in Applications > Utilities) and run the following command:

   open $TMPDIR../

   The folder that opens is the temporary directory the system has assigned to your user account, which applications use as a scratch folder for brief settings changes, downloads, and other temporary items. In here, go to the “C” directory (for Caches), and remove any file or folder following the same naming scheme of “com.COMPANY.APPNAME.” Do the same for items in the “T” directory (for Temporary items). Note that you can remove the entire contents of this directory without harm to any of your data or applications, but it may be best to start by removing the items pertaining to your specific program.

Next steps…

Beyond these approaches, problems with your apps may require more specific troubleshooting to clear, as they can be from odd problems with system service configurations, or conflicts between installed applications. These can be addressed by examining log files while you open the application, or performing specific configuration changes to apps per developer support instructions. At this point you might need to contact support lines and The steps may take some investigating to figure out; however, do keep in mind that in most cases supported apps should eventually work.