My wife, Linda, has a laptop that failed for the last year to apply the updates to Windows 10 rev 1903. The latest rev should be 1909. When the updates tried to apply manually or automatically, the progress would get to 98% and then fail. The message said it could not be updated but gave no reason.
I had updated my tablet PC to 1909 by searching for the Microsoft Windows 10 Install web page and updating from there. I decided to try that technique for the laptop although an Install can preserve data files, but application programs would have to be reinstalled. That would include Office 365, now renamed Microsoft 365, for which we have a multi-device subscription. When I tried that install technique, I received a better diagnostic message. I learned that it “could not update the System Reserve Partition”.
I searched for that message online and found:
That gave detailed command-line instructions for naming the partition as drive Y: and how to set the access controls so I could delete extra files and what files to delete:
Windows 10 with MBR partition
- Press Windows key + R. In the Run window that comes up, type diskmgmt.msc and press Enter.
- Select the partition marked System Reserve. Press-and-hold or right-click on it.
- Select Change Drive Letter and Paths.
- Choose Add.
- Enter Y for the drive letter.
- Tap or click OK.
- From the Start menu, search for cmd. Right-click Command Prompt from the search results and select Run as administrator.
- In the command prompt, type Y: and hit enter to switch to that drive. Then, navigate to the Fonts folder by typing cd Boot\Fonts.
- Type the following and press Enter:
takeown /d y /r /f .
Note: You must include the space and the period after the “f”, or the command will not work properly.
- Back up the permission to the drive by typing the following and press Enter:
icacls Y:\* /save %systemdrive%\NTFSp.txt /c /t
Note: Make sure that all files are shown as successful. One failed but that was OK.
- Type whoami and press Enter, and then record the username. Type the following command and press Enter:
icacls . /grant <username you got from whoami>:F /t
Note: Do not put a space between the username and “:F”, or the command will not work.
- Make sure you are still located in Fonts location (Y:\Boot\Fonts) as described in step 8. Then, Type del *.* to delete font files. The system may ask you if you are sure to continue, press Y and then enter to continue.
Restore permissions
- Type the following command and press Enter:
icacls Y:\ /restore %systemdrive%\NTFSp.txt /c /t
- A message may display indicating some files failed while processing – this is normal because these files have been deleted after backing them up.
- If the amount of successful files is none, then the command was executed incorrectly; you must have some files successfully processed before continuing.
- Adjust the ACL back to System by typing the following and press Enter:
icacls . /grant system:f /t
- Set the owner of the drive back to System by typing the following command and pressing Enter:
icacls Y: /setowner “SYSTEM” /t /c
- Go back to Disk Management and Refresh the data to confirm if the SRP now has a greater percentage of free space. If so, the drive letter can be removed at this point.
- Right-click the System Reserved Partition.
- Select Change Drive Letter and Paths.
- Choose the Y: drive.
- Select Remove.
- Click OK.
Next, I tried to upgrade the system again, but it still complained about not having enough space. I went back to the instructions above and instead of DEL *.* in the Fonts directory, in the Y:\Boot directory I deleted the folders of some languages that we would never need, such as Russian and Swedish, etc. After each, I checked my progress with the DIR command, which displays the amount of free space on the Y: drive. I also deleted memtest.exe, which is big. I made sure that the free space exceeded 15 MB. I restored permissions again and then successfully ran the latest update, which took rev 1903 up to 1909.