Why does Preview app .fail to open ?

Question

When trying to open up an image using preview, I keep getting a message  ' The application "Preview app" is not open any more '.Consequently any image I try to open fails- The only way I have found to temporarily restore the application is to shut down & restart the computer ( not very efficient !!) but the problem reoccurs.
I have reset the PRAM and also reinstalled my OS X 10.10.2 Yosemite to try to get over this but to no avail..
Any suggestions would be most welcome

Answer 1

Launch the Console application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad and start typing the name.
The title of the Console window should be All Messages. If it isn't, select
          SYSTEM LOG QUERIES ▹ All Messages
from the log list on the left. If you don't see that list, select
          View ▹ Show Log List
from the menu bar at the top of the screen.
Click the Clear Display icon in the toolbar. Then try to launch Preview. Select any messages that appear in the Console window. Copy them to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.
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