Tom wanted to learn Linux, so he loaded up Linux on his PC. After a month, Windows now wants to install a feature update 1903 and now he's lost a partition. Leo says that Windows is being "bossy," thinking that it's the only OS you should have. So it "clobbers" your boot record and causes a boot-up issue. It's a common, yet complicated issue. You need to have a boot manager to sort it all out. Leo recommends GRUB. It gets loaded first and then asks you which OS you want to use. Most likely, the update redid the master boot record, damaging it.
Charles would like to create a dual boot system on his laptop with Windows and Ubuntu Linux. How can he do that? Leo says that running Linux on his computer is a great journey and it has become a lot easier to create a dual boot system with Ubuntu. All he needs to do is download the installer to a USB key and then boot to it. Then it will walk him through creating the dual boot portion. Then when he boots up every day, the GRUB boot manager will ask him which OS he wants to load.
Greg has a recommendation for the rEFInd boot manager, which is a fork of the rEFIt project. Leo says he's been looking for a boot manager designed for UEFI and EFI that will work with modern operating systems.
Andrew wants to add an SSD to his laptop. Can he just swap out the optical drive? Leo says if it's a Mac, he can. MacSales has an enclosure just for that purpose. So if his laptop supports that feature, he's golden. The key is the enclosure.
Robert installed a second version of Windows and now he can't get it to boot up to the newer Windows 7. Leo says that's because Windows always boots up the latest installed OS. Leo advises using a boot manager to choose operating systems. Leo uses GAG.