We have a HP F380 All-in-one Printer/Scanner/Copier. Occassionally, it just goes offline for some reason (the printer icon in the Printers and Faxes window is translucent, and it says Offline; needless to say it doesn't print and the print jobs just get queued), and it stays offline even if Work Offline option in the Printer settings is unchecked. Tried power cycling or unplugging and replugging the USB port. The weird thing is, if the printer is disconnected or turned off, the Printer icon has the words "Offline-Offline" under it (!), whereas if the printer is connected and turned on, it says just Offline once. So far the only solution to this strange occurance is to restart Windows, which I don't want to have to do every time.

Anyone know what causes this? Couldn't find any answers at HP's website.

Did you try this troubleshooting tree from the HP support page?

I have an all-in-one printer and used to have similar problems. The only way i got it to work was to reinstall the printer.

My printer did the same thing. I got onto one of those chat support things and I got the solution. First un plug the USB connection in the back of the printer; then go to Start>>run. Then type in "service.msc" and enter. A service window will come up. Scroll down and locate the print spooler - right click & select restart. It only took a second or 2 and then I reconnected the USB cable and was able to print again.

I hope this works for you