I had in my mind that I was going to spend some of my free time today getting the Windows 7 Ultimate side of the dual boot on my main desktop prepared for Windows 10. But I noticed something else booting back and forth between 7 and 8. The boot times going into Windows 8 were normal, but it seemed like the logon times were pretty sluggish. I have a couple of drivers that are delayed load, but they don’t interfere with using the PC as soon as the desktop is visible.
But it was unresponsive for a few seconds, which is unusual. Sfc /scannow found errors it couldn’t fix, so I ran DISM.exe /Online /Cleanup-Image /RestoreHealth. It couldn’t get the image (it couldn’t connect) from Windows Update (which is the default), and even when I defined a source path to a mounted ISO file, it still couldn’t find the image. The error code was consistent, 0x800f0906. There are a number of solutions for this error code, which is associated with .Net 3.5 installation and also with corrupt image file un-locatable source issues. I tried all that I came across, but always received the same error code. Nothing that I found worked.
My conclusion (I have nothing to back this up) finally came down to the probability that the Deployment Imaging and Servicing Management tool was itself corrupt. Long story short, I used a drive image from April 10 where the DISM tool actually worked. That left me with over 100 Windows Updates to install, which I did in groups of 10. After each group, I ran DISM.exe /Online /Cleanup-Image /RestoreHealth. After the third set, it found and repaired corruption in the image. All the rest looked like this last one:
I think I’ll be a little more regular in running sfc /scannow as part of my routine maintenance. A system that has a bit of corruption in it can still make a good drive image with no indication of anything amiss. If sfc /scannow comes up clean, then it’s a pretty good bet that the system is clean, and a drive image will more likely be reliable and trouble free.