Exchange OWA users are unable to open or save attachment from OWA with IE8/IE9

Here is how to change with a GPO:

Machine Policies > Windows Components > Internet Explorer > Internet Control Panel > Advanced Page >

Do not save encrypted pages to disk

Policy Details

Policy Class Machine

Supported On At least Internet Explorer 6.0 in Windows 2003 Service Pack 1

ADMX File inetres.admx

Requires Reboot False

Requires Log Off False

Registry Location

HKLM\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings!DisableCachingOfSSLPages

Official Explanation

"This policy setting allows you to manage whether Internet Explorer will save encrypted pages that contain secure (HTTPS) information such as passwords and credit card numbers to the Internet Explorer cache, which may be insecure.

If you enable this policy setting, Internet Explorer will not save encrypted pages containing secure (HTTPS) information to the cache.

If you disable this policy setting, Internet Explorer will save encrypted pages containing secure (HTTPS) information to the cache.

If you do not configure this policy, Internet Explorer will save encrypted pages containing secure (HTTPS) information to the cache."

Here is the settings in Internet Explorer options:

The GPO Setting:

Machine Policies > Windows Components > Internet Explorer > Internet Control Panel > Advanced Page >