If you're a bit behind on your Windows 10 upgrades and are now looking to install either the Windows 10 May 2020 Update, or the latest October 2020 Update, we have some news for you. Microsoft has added a new upgrade block or "hold" for these newest versions of the operating system, related to Thunderbolt NVMe SSDs.
According to the release information page for both the October 2020 Update, and the May 2020 Update, Microsoft and Intel have recently discovered this incompatibility issue on certain devices (via Neowin). Apparently, when a Thunderbolt NVMe SSD is plugged in on PCs running these versions of Windows 10, you might end up with a stop error with a blue screen and "DRIVER_VERIFIER_DMA_VIOLATION (e6) An illegal DMA operation was attempted by a driver being verified" message. This occurs only on devices with at least one Thunderbolt 3 port.
Microsoft has an interesting note and mentions that the hold only applies on "Windows 10 devices with affected drivers or firmware from being offered Windows 10, version 2004 or Windows 10, version 20H2." With this language, it is not clear if this is only for specific Windows 10 PCs with Thunderbolt 3, but we assume it is.
Microsoft says it is working with Intel on this and a fix could come in an upcoming release. We're hoping to see it on Patch Tuesday, which should be this coming week on November 10. In the meantime, if you're on these versions of Windows 10, you should not manually attempt to install either the May 2020 Update, October 2020 Update. That's either through Windows Update, or the Media Creation Tool.