Thumbnail on .pdf shortcuts

Silly question. If I create a new .pdf shortcut, it has the standard .pdf icon. Over the course of several days (including reboots and sometimes opening of the .pdf file), it may or may not change to a miniature of the first page of the individual .pdf.
I do not really care, but can someone tell me what governs that?

Possibly useful link:

http://answers.microsoft.com/en-us/w...2-3c9b69d5ebfd

jdc2000--Well you hit much of the nail on the head. The link you provided describes my situation exactly. And Corinne's and Minghung Cho's posts almost solve the issue.
If I open Reader and click File and then Open, the thumbnails are created within Reader for all the .pdf files on Desktop. However if I go back to the Desktop itself there is no change in which .pdf files have thumbnails. Some do and some don't. I guess I will just have to wait and see which eventually get the thumbnail.
Interesting.
Thanks.

This is likely another case of Adobe blaming Microsoft and Microsoft blaming Adobe. There is probably plenty of blame on both sides.

Did you try rebuilding the icon cache?

1. First make sure you have "Show hidden files, folders, or drives" turned on.
   1. Click the Start orb, type in:
      
      
      
      folder
      
      
      and select "Folder Options" from the list.
      
      
   2. Click the View tab, select "Show hidden files, folders, or drives" and click OK.
   
   
   
2. Now to rebuild the cache file.
   1. Click the Start orb, type in (or copy and paste):
      
      
      
      %userprofile%\appdata\local
      
      
      and press [Enter].
      
      
   2. Rename the "IconCache.db" file to "IconCache.db.old".
      
      (Simply append ".old" [without the quotes] to the end of the filename).
      
      
   3. Close the window, and restart the computer.

SpywareDr--Thanks for the idea. No, I did not use the iconcache.db repair. As mentioned, the .pdf Desktop shortcut icons generally become thumbnails over a period of time. Today 8 of 9 .pdf shortcuts show the thumbnail. And, even several days ago when I accessed Desktop through Windows Explorer, all the .pdf icons were thumbnails--just not on Desktop, itself.

I don't know. Still sounds like something to do with the icon cache file to me.

Only takes a minute or two to rename it, reboot and let Windows to build a new one.

If it works, great. If not, it's certainly not going to hurt anything.

<-shrug-> :)

Finally, the fix
http://forums.adobe.com/message/5726890

Explanation of what the problem was. Reader 9+ did not play nice with Win 7 64 bit.