My Windows 10 Pro 1803 release only has 256MB of System Reserve area. After making all the update changes to 1803, I started the 1903 update which ran fine until it said the System Reserve area was to small. The new 1903 needs at least 450MB of Reserve Area. I have a system with a 320GB hard drive and have room to spare. My question is how can I increase the size of my system reserve area to around 600MB? I had backed up my system and used a free software package called Mini Partition Magic. I shifted my system partition to make room for the extended System Reserve area and ran it. Twice the Windows system 10 Pro fails to complete and I lose both my original system reserve area and my Windows system 10. I have a cloning software so I can rebuild my 320GB hard drive. Now I'm updating the 1903 Windows 1o Pro, but what do I do when it sends a message that the System Reserve area needs to be extended?