I answered, or rather commented, elsewhere....
This has also been happening to me and only started happening recently.
From my observations, it is not due to anything local but rather App Store seems to be causing downloading several tens of megabytes of stuff from Apple web sites (developer.apple.com, among others) and also seems to involve the program ocspd.
Apple, we await a fix from you....
The v10.6.7 combo update includes some MAS bug fixes that may help.
Restart your Mac after the combo is installed.
It's ok to do this even if you are already running v10.6.7
From your Applications folder move the App Store app to the Trash. Empty the Trash.
Now open a Finder window. Select your Home folder in the Sidebar on the left then open the Library folder then the Caches folder.
Move the com.apple.appstore and the com.apple.storeagent files from the Caches folder to the Trash
From the same Library folder open the Preferences folder.
Move these files Preferences folder to the Trash: com.apple.appstore.plist and com.apple.storeagent.plist
Same Library folder open the Cookies folder. Move the com.apple.appstore.plist file from the Cookies folder to the Trash.
I know you already installed the v10.6.7 combo but you need to do this one more time. If you still have the original .dmg file, move that to the Trash.
Reinstall new: http://support.apple.com/kb/DL1361
If that didn't reinstall the App Store app, follow these instructions.
Pacifist is a utility that can extract files from a .dmg folder.
Open Pacifist after you install it. In the Pacifist window click Open Package.
Navigate to the MacOS XUpdCombo10.6.7.pkg. Select that then click Open.
In the next window click the gray disclosure triangle where you see: Contents of manual
Then click the triangle next to: Contents of MacOSXUpdCombo10.6.7.pkd
Then click Applications, then right or control click: App Store.app
Then click: Install to Default Location. That will reinstall the MAS to your Applications folder.
Thanks for trying to help Carolyn, unfortunately after doing all of the above it is no better.
The Mac App Store came back up on its own after reinstalling the v10.6.7 combo so I didn't need to go the 'Pacifist' route.
I have timed the application carring out particular actions as follows, before doing this I closed absolutely every program that was running on my iMac and anything running in the background (Dropbox etc):
My own account (best time recorded)
Time to open after clicking icon in dock = 1 min 16 secs
Time to switch from 'Featured' tab to 'Top Charts' = 1 min 14 secs
From a new test account
Time to open after clicking icon in dock = <5 secs
Time to switch from 'Featured' tab to 'Top Charts' = 2 secs
This is starting to make me paranoid, as I can't understand why most people have no problems with the App Store.
I don't suppose this has anything to do with it but here goes:
I have a warning dialogue that has been popping up every hour or so for the last few months, I don't know what app is causing it so I just click 'OK" and it disappears for a time.
This is the dialogue:
Puzzled ??? I know I am.
The painfully slow behavior of Mac App Store is related to a security setting in the Keychain Access, namely the "Certification Revocation List (CRL)".
If you are willing to disable it (if I'm not wrong, it should be off by default), the MAS application will regain the original responsiveness.
To modify the setting in question:
- Quit the Mac App Store application
- Open Keychain Access > Preferences > "Certificates" Tab
- Set "Certificate Revocation List (CRL)" on OFF
- Close the Keychain Access' Preferences pane and quit it
- Open Mac App Store