Outlook – Does Outlook 2010 support IMAP push or not

If somebody is still looking for a solution, hlpPy's solution above works for IMAP PSTs as well, I just tested with Outlook 2010. It is a non-technical solution anybody can follow without having to mess with the registry, but you need to follow it exactly:

• Start –> Control Panel –> Mail.
• Click on the "Data Files..." button at the left.
• Click the "Data Files" tab at the top if it is not already selected.
• Select the Gmail data file you want to move, its name should be your e-mail address.
• Click "Open File Location..." in the options above (do NOT close the Mail applet after this! If you close it and reopen it, it will re-create the files, this is why most people are having issues)

• In the Windows Explorer window that opens, cut the highlighted .pst file and paste it in the folder where you want to move it to. Leave the .obi and other files in the same location.

  DO NOT OPEN OUTLOOK JUST YET!

• After moving the PST, go back to the Mail applet that should still be open and double click the highlighted Gmail data file (it should still be highlighted)

• You will get a warning saying that the .pst file cannot be found. Click OK. Now you will be able to browse and redirect to the new location where you pasted the PST file.
• Close the Account Settings window and Open Outlook.

It's possible to move MS-exchange pst file in the same manner, but before selecting new location, you should disable Cached Exchange Mode and disable Offline use. After you've selected your new file, you may re-enable this features.

Found it:

Outlook Preferences -> Schedules -> Double click Send & Receive All -> Go to your account under "Action" -> Click here for account options -> Make sure the folders are selected for syncing.