Adobe Reader X includes a feature called "Display in Read Mode by default." This feature is checked off by default which causes the Adobe Reader toolbar to be hidden when opening any Adobe PDF.
Hovering your mouse over the top center of a PDF will display an Adobe mini toolbar, allowing you to print the PDF.
You can also change the setting within Adobe Reader to force the toolbar to appear whenever you open a PDF.
To force the toolbar to automatically appear on all PDFs, please do the following:
Open Adobe Reader X
Click on Edit and select Preferences in the upper left hand corner.
Click Internet from the left side bar.
Uncheck Display in Read Mode by default.
Click OK button.