I've just signed up to ask a question, but before I do I'd like to say that Terry60's pinned post "Please read before posting" explained some things to me that I'd never had explained before, e.g. the Disk Management "System flag" and "Boot flag". In fact, they probably explain why I have my current problem. Also, the "Multibooters.co" article is brilliant. I'll need to read it again 4 or 5 times to absorb all the good stuff in it. My problem: I've got 5 computers on my home network: some old, some newish. Three of them dual boot XP and Windows 10. One is XP only (my main one <sorry>), and one has two Windows 10 installations on it. This one - a laptop - is the one that has the problem. The first Win10 partition is faulty - the other computers on my local network cannot see it, so I want to delete this first partition. This partition has the following flags: System, Active, Primary Partition. The next partition has no name and has this flag: Recovery Partition. The next partition is named Data and has this flag: Primary Partition The next and last partition is named Win10New and has these flags: Boot, Page File, Crash Dump, Logical Drive. This installation is fully up to date, works perfectly and can see all the other computers and they can see it. I want to delete the first partition because I like to make System Images frequently, and the extra 35 GB used by the faulty Win10 partition wastes imaging time and could be used to increase my Data partition. What I tried was deleting the first partition using Partition Wizard 9. This is my favourite partition manager which I've used many times in the past, booting it from USB, but never to delete the first partition - usually to create a second one from unallocated space and then create a data partition or for installing another version of Windows in. You're probably chuckling to yourself already because you've guessed what happened - the system became unbootable. So I restored the System Image that I'd made beforehand and I'm back to a working system. So the question is: how do I delete the first partition, not delete the MBR, and not mess up the booting?