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Struggling with iSCSI Boot Errors? Here’s the Windows Server 2025 Fix You Need!
You’ve just installed Windows Server 2025, feeling ready to dive in, but then your server won’t boot. Instead, you’re staring at an error: “Boot device inaccessible.” Let’s break it down simply and fix it fast.
Servers using iSCSI (Internet Small Computer Systems Interface) technology ran into a nasty bug after installing Windows Server 2025. This issue popped up when servers booted from an iSCSI LUN while running in NDIS poll mode. A boot failure accompanied by that dreaded error message.
This wasn’t some isolated glitch. It was widespread enough for Microsoft to confirm it as a known issue shortly after the OS launched in November 2024.
Why Did ‘Boot Device Inaccessible’ Error Happen?
Think of iSCSI as the middleman between your storage and your server. When something disrupts this connection—like a misstep in how the OS handles boot processes—you’re left with a server that can’t find its footing.
How to Fix ‘Boot Device Inaccessible’ Error?
Microsoft patched this issue on February 11, 2025. If you’re still seeing the error, here’s what to do:
Solution 1: Install Update KB5051987
This update resolves the bug and includes other critical fixes for Windows Server 2025.
Solution 2: Check for Later Updates
Always grab the latest updates to ensure your system stays stable and secure.
Solution 3: Verify Your iSCSI Configuration
Double-check that your server is correctly set up for iSCSI booting, especially if you’re in NDIS poll mode.
Skipping updates is like ignoring a leaky roof—it only gets worse over time. Microsoft’s February patch doesn’t just fix this specific problem; it also addresses other stability issues you might not even know about
Pro tip: Stay on top of updates to avoid future headaches.