There is a strange adobe acrobat reader error popping up around the place that just pops up with a blank error box with a question mark and no clue to what the error is.
It looks something like this
The error usually occurs when you try and open a pdf file from within your web browser, try different browsers to see if its only happening with a particular browser (most common for internet explorer and mozilla firefox)
Steps to correct this issue
1. Update Adobe Acrobat Reader
open up adobe acrobat reader click Help -> Check for Updates you may need to restart your computer
2. Reinstall Adobe Acrobat reader
uninstall and reinstall adobe acrobat reader, the issue is sometimes caused by a bad pdf plugin in your web browser. try switching web browsers and reinstalling the pdf plugin.
3. Uncheck open PDF within web browser
this will usually fix the issue instead of choosing to open the pdf within the web browser itself, the pdf file will just open up acrobat reader before trying to open the file, pretty much the same thing anyway
Edit - > Preferences -> Internet Tab
