The support document says Windows 10 users with external USB storage or SD cards in use may not be able to download Windows 10 May 2019 Update. Microsoft says an “inappropriate drive reassignment” is causing the problem. “Inappropriate drive reassignment can occur on eligible computers that have an external USB device or SD memory card attached during the installation of the May 2019 update,” Microsoft said. “For this reason, these computers are currently blocked from receiving the May 2019 Update.” Users with SD cards or USB storage devices will be greeted with the following message if they try to install version 1903.
Microsoft says it is working on fixing the problem. The company says a solution will not arrive until a future Windows 10 servicing update. It is also worth noting, the problem is only for users coming from the April 2018 Update or October 2018 Update.
Working Method
As noted, this situation shows why the company’s new update strategy works. Under the previous schedule, Windows 10 version 1903 would already be available as the April 2019 Update. Users with external storage would have been hit with problems. Because Microsoft is now delaying updates, the company was able to spot the problem and take action. Sure, that action is inconvenient for a subset of Windows 10 users. However, it means the company does not have to pause an update.