When something goes wrong with your OS X operating system or your Applications you can try several things before getting upset about it:

Quit all unused apps – If you have a memory issue this will solve it. Restart – Most of the times this is a quick solution. Repair permissions – Open Applications/Utilities/Disk Utility, select your HD and Verify then Repair your Permissions. Verify your HD – You should do this if you’re suspecting a failing HD, if confirmed backup and replace! Update your System – Run Software Update from the Apple menu. Update your misbehaving App – Check if the app you’re having trouble with has an update and apply it. Reinstall your App – this may fix problems with corrupt application files. Do a safe boot – Restart while holding down the Shift key – this operation will do many different operations that may heal a sick Mac. Create a new user – Logging into a new account will show you whether the problem lies in your system or just your account. Trash Preferences or Cache – Trash your application and/or system preferences that are located under user/Library/Preferences and user/Library/Cache. You will of course your lose the application or system settings, but it may fix the issue. Disable or delete plug-ins – If you have more than one plug-in installed with your App they may have a conflict. These plugins are to be found under user/Library/Application_name/Plug-ins. Some apps, like Firefox has a built in plug-in manager that you can use. Rebuild the database – Many applications with large databases may benefit from restarting them with the Apple key pressed. Check your Preferences/Accounts/Login items and delete as many items as you can. Fix your keychain – You can rebuild your keychain if you have password problems by going to Applications/Utilities/Keychain Access then select File/Keychain First Aid Google the problem – Try different keywords to search for the particular problem. Chances are the fix is already documented somewhere. Ask on support forums – There are plenty of helpful people on 

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