One of the new features in OS X Lion and OS X Mountain Lion is the “Resume” ability for all applications to save their last state, meaning when you relaunch the app or reboot your Mac, the application will “resume” and reopen again showing all of the windows and data that was last in use. This is a great feature for some apps and situations, but there are also times where you don’t want past app states to reappear.

How to Delete Saved Application States from Resume on a Per App Basis in OS X

This tip will show you how to selectively remove saved app states for chosen applications. You can think of Resumes saved state files much like cache files, they will be regenerated upon an apps use, so deleting them is not permanent and only affects the last saved state.

Quick Note: This tip accesses ~/Library/ which is hidden by default in Mac OS X Lion and beyond. You can use Command+Shift+G to “Go To” the folder ~/Library or, if you want to, you can change Lion to show the user Library directory with a simple entry into the command line.

Navigate to ~/Library/Saved Application State/ – this is easy with Command+Shift+G

You’ll see a list of saved app states named com.apple.(Application Name).savedState

Delete the folder pertaining to the application whose saved state you no longer want to maintain

Keep in mind this is a temporary solution, as mentioned before, Mac OS X 10.7+ recreates these files upon each applications launch. Your only other option would be to disable Saved Application States completely, but most people find the feature useful enough to not want to do that. If you wanted to you, you could remove all of the files in this directory as well.

Deleting Resumes Saved App States in Lion Often? Create an Alias

If you find yourself doing this frequently, you may want to create an alias on your desktop for the “Saved Application State” directory, then you can quickly remove the saved states that you don’t want to maintain.

Chances are good that some apps will include options to disable this feature natively, or at least a third party solution will appear that allows per-app for preserving or preventing saved states. Until then, this is a perfectly viable solution.

Thanks to Randy for sending in this great tip.