Comment 36 for bug 478761

Hi Davias,

Something about the xsane driver seems to put my scanner into an odd state wherein I also get the "invalid argument" error message and cannot scan. At first I thought it could be a number of things (see comment #30), but I've definitely nailed it down to hardware state issue.

Normally, the main LED indicating the scanner is powered on and ready is either fully-lit green or off. When the scanner gets in this odd state, however, the LED is either off when the USB cable is unplugged or "half-lit" green. Switching USB ports, switching from one Ubuntu machine to another -- nothing fixes it. I've found that the only way to correct the problem is to hook the scanner back up to a WinXP box and then run some application that activates the manufacturer's driver (in my case, the Epson Scan Utility). I don't even have to scan anything -- I just need to ensure that the main LED becomes fully-lit green again.

Eventually, under Ubuntu the scanner LED goes half-bright again and, notably, thereafter the scanner *no longer* resets itself twice after reboot (i.e., normally, I can hear the scanner resetting twice during reboot -- this is true for when its connected to WinXP and it is true when its connected to Ubuntu and when xsane will subsequently work). I'm still not clear on when and why the scanner gets into this state, but eventually I will and will then post here.

My scanner is an Epson, not a Brother, and I'm running 9.10, not 10.04, so my problem and workaround may not be of help to you, but I'd be curious one way or another.

My suspicion is that either xsane, some of its drivers, or some Ubuntu USB driver put or leave the scanner hardware in some odd, non-functional state. The reason I say this is, not only does my scanner LED turn half-lit green when the problem it starts, it *stays* that way no matter what: hard reboot of the machine, removing power from the scanner, doing both at the same time, doing both in the two possible orderings, etc. Nada, nothing, nichts. The *only* way I have found to "reset" the scanner is to have the manufacturer's drivers interact with it. Very odd indeed.

Next time this happens, I'm going to try running the Epson Scan Utility on WinXP under VirtualBox on the Ubuntu machine to which my scanner is normally connecting. I don't know if it will work or not, but it'd be nice to be to fix this problem on the fly w/o having to reboot or physically move the scan.

Anyway, my apologies for the long post. I hope this information can be of help to you or others.

Cheers,
Doug