When the dialog box opens, no icons appear. Instead, there is a green "progress bar" running from left to right on the top of the box. It takes minutes to almost reach the right side of the box - then goes no further. Thus, I can't use the "Devices and Printers" dialog box.
Have a look at this Seven Forums solution. It might work for you as well. Make sure you read Ztrucker's method in post #5 & follow it though as described.
Devices and Printers won't load. No start menu programs.
Another solution that worked for me is: Shut off any printers or devices (attached or wireless) and disconnect any devices that are plugged into USB ports. Restart your computer and open "Devices and Printers." If it now opens, restart your computer - then turn on/attach any external devices and re-plug any USB devices.
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