Okay. So, I tried both of the approaches in
Install CAB file in Windows 10, but they didn't work. In both cases, I got the same error I had seen previously: "The system cannot find the file specified."
However, something I read there gave me an idea, so I tried a totally different approach, and it ended up working. So, thank you for your persistence on suggesting that I keep trying! Previously, I had been using the native ability of Windows Explorer to view and extract the contents of the .cab file. This turned out to be a bad choice. Apparently, Windows Explorer does not preserve the directory structure in the .cab. Therefore, it is imperative to use 7zip, WinRAR or some other archive program to extract the files properly. I used Zipware to do it. Once I had the .cab extracted properly, I was able to install the driver manually.
Here are step-by-step instructions for anyone else who needs to do this:
1. Access the Microsoft Update Catalog with
https://www.catalog.update.microsoft...rch.aspx?q=6mp
2. Choose the fifth item in the catalog list and click the "Download" button. This will allow you to download the file 4188_bacd1413e93b4a6362d9a2ca653c869f1c02f6f7.cab
3. Use 7zip, WinRAR or Zipware to extract the .cab file to a folder.
4. In Windows 10 settings, go to Printers & Scanners, select your LaserJet printer and click "Manage"
5. Click "Printer Properties" and then go to the "Advanced" tab.
6. Click "New driver" then "next" and "Have disk". Then browse to the folder where you unzipped the .cab and click "open" then "ok". A list of printers will appear. Scroll down to "HP LaserJet 6MP" or whatever your printer is. Click "next" and "finish" and then you will be good to go!
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