Weird behaviour with usb drive

Thanks for the suggestion. I appreciate your willingness to help with this.

When I look at that setting on the mini-computer, there is only one option under usb because the mini-computer does not have a battery. Unfortunately I already disabled that earlier when trying to solve this and it didn't help. However, the link you provided made me wonder about the usb power settings under Device Manager so I took a look at those and they were all Enabled (Generic usb hub, usb 3 extensible host controller and usb root hub) so I disabled them as well. I don't know yet if this will make a difference but I will certainly let you know if it does.

 

Since I disabled all the usb power settings the drive has been working correctly. After being caught out by this before, I want to give it another week or so just to make sure before marking it resolved again, but so far it looks promising.

One thing I don't understand: If these settings cause the computer to turn off the usb drive, why doesn't it come back on when I click on it? Shouldn't it power up when it is accessed? It shouldn't take more than a few seconds to spin up the drive but that is not the behaviour I am seeing. With or without the Ribbon of Death, the drive simply does not respond, even after several minutes. The only way to get it working again is to unplug and replug it. Why is this so?

 

OK, I spoke too soon. The problem has not gone away. I had been quickly checking the drive's file list in Explorer after booting as a way of verifying drive accessibility (I have an Explorer shortcut to the root of the drive on the Desktop). This morning I needed to copy a file from the drive and the same problem occurred. For some reason I am now seeing the list of files (maybe cached?), which was not working before, but I still get the same error when I actually try to click on a file or folder in the list.

This time I checked the Windows log files for errors that occur each time the computer is booted up. I found the following but I don't know if any are significant for this problem:

perflib error, BITS open failed, bitsperf.dll
Device Setup Manager Service hung on starting
Wlan extensibility module failed to start
Dcom errors, server did not register

After checking the log files, I opened Disk Management. It took a long time before the program opened, about 10 or 15 seconds, but it did eventually open and I could view all the details of the USB drive, which appeared normal. I then tried opening a file on the drive and it worked normally! This is the first time I have been able to access a file without replugging the drive. I think the delay was normal, because most of the files on the drive, many gigabytes, are large video files and it takes time for Windows to read through them, especially as the drive is only USB 2.0. I have seen the same behaviour with large USB drives on other computers so I don't think this is unusual. The big difference is that i was able to get Windows to read the drive at all without replugging it, which is the first time I have been able to do this. What this tells me is that Explorer cannot access the drive for some reason, but Windows can if I do it via Disk Management. After that Explorer works normally.

I still don't know why this is happening and what I have to do to fix it, but I am providing as much information as possible in the hope this will help someone else figure out what is going on. Thanks again for reading.

 

It has been a few days since my problem with the inaccessible usb drive last occurred. The power has been switched off and on several times and each time the drive is immediately accessible from Explorer after the computer boots. I was about to mark this thread, if not resolved, at least concluded. Yet today the problem happened again. I switched the computer on and after booting I got the dreaded 'drive not accessible' error. I tried several times in different ways but Windows steadfastly refused to read the drive.

I have no idea why this has occurred. Nothing has changed on this computer in the past week. To test it I have been starting it up in exactly the same way each day. I haven't added or modified anything. There is no logical reason why it worked yesterday and not today.

However I have now discovered that I can force the drive to start by using Windows Disk Management. If I click on that all drives, including the usb drive, are displayed after a delay of about 10 seconds. If I then click on the usb drive, it works normally.

This is not exactly a fix, but it does offer a way to get the drive going again with having to go over to the computer and physically replug the drive. If nothing better turns up I am prepared to accept this as a kind of solution. I will wait another day or so for any more comments and then mark the thread as 'resolved'.

 

The last time I booted up the computer the usb drive worked fine. Again, nothing had changed. I guess this is just another one of those many Windows quirks that will never be adequately explained.

I want to express my gratitude once more for the time and effort you and others here have put in to trying to help me solve this very perplexing issue. It helps a lot to have other knowledgeable people share the problem.

I may try the clean boot at some point just to see what happens, but I can live with things as they now are. Disk Management gives me a workaround for when the problem occurs. I guess that is good enough.

Thanks again for the help. This issue is now Resolved.