Screenshot which you have posted that is for your browser did you tried to open PDF in Adobe Reader X
If they do not open automatically then try this :
Open your Adobe Reader X and click on Edit -> Preferences -> Internet
On the right hand side, Display PDF in browser should be unchecked :
Hope it helps !!
Hi. It is unchecked and it still happens. This is so incredibly frustrating.
You might try to turn off and video acceleration for your video card. A less likely option is to turn off protected mode.
As I can see in the screenshot,you have Reader 9.As you told it is updated,so I assume you have latest Reader 9.4.3.
Please try by installing Reader X and check the same pdf or other pdfs from the same source.You can download reader X from http://get.adobe.com/reader/
If you face same issue with Reader X also,it is possibly some issue with your visual/graphic settings.In that case please try what MichaelKazlow has suggested.