Fixing Windows 7 and finding lost data

Q: In January, I upgraded my Dell Windows 7 laptop to the "assistive technologies" version of Windows 10, which is designed for people with disabilities. After five days, I decided that I preferred Windows 7 and tried to revert to it. However, Windows 7 failed to start and I got the message: "A required device isn't connected or can't be accessed; Status: 0xc000000f." It also said I could insert the Windows 7 installation disk to proceed.

But I don't have a Windows 7 disk. I didn't get one with the PC, I never made one and Dell says my five-year-old PC no longer qualifies to download a copy of Windows 7. Can I make a Windows 7 backup disk on my desktop PC that I can use on the laptop?

Larry Salzman, Minneapolis

A: When downgrading goes awry, there are some free ways to fix the problem. For you, the easiest method is to use your desktop Windows 7 PC to create a "system repair disk," then use the disk to fix Windows 7 on your laptop.

(Why not just create a Windows 7 installation disk with your desktop PC, then reinstall Windows 7 on the laptop? Because Microsoft makes it difficult to copy Windows from one PC to another.)

To create the system repair disk, click the Start button on the desktop PC, choose Control Panel and click "system and security." Then click "backup and restore." On the next screen, click "create a system repair disk." The repair data is then copied to a blank CD or DVD disk.

Put that disk in the laptop's CD or DVD drive and restart the PC. If necessary, press any key on the keyboard to make the PC boot up from the system repair disk. When prompted, choose your language setting and click Next. Then select "start-up repair" and click Next.

Q: Before my Windows 7 PC crashed, I had backed up my data to an external hard drive. But now I can't transfer those files to my new Windows 10 PC. All the backup file names end in ". wim," and I don't have a program that will open them. What can I do?

Ted Richert, Miami Shores, Fla.

A: Your files are accessible. The problem is that you've used the wrong backup process. Instead of backing up just your individual files, you've created a "system image" of the entire Windows 7 hard disk. That image (. wim stands for stands for Windows Imaging Format) contains not just your personal files, but the Windows 7 operating system and all your PC programs.

That's useful if you'd needed to completely restore the hard drive on your Windows 7 PC. But it can't be used on a different computer. So, the only way to retrieve your data is to open the . wim files and copy the personal data that's currently locked inside.

To open the files, download the free program "Easy 7-Zip" at tinyurl.com/h5wk9bp. Then go to tinyurl.com/jsr9wzz and read the directions under "Open/Extract WIM File on Windows."