0XC0262115: Allocation device mismatch fix

Why this error happens

Windows throws 0XC0262115 (ERROR_GRAPHICS_WRONG_ALLOCATION_DEVICE) when a DirectX or graphics API call tries to use a GPU memory allocation that belongs to a different device. This usually means one of three things: your graphics driver is stale or corrupted, a specific app is holding onto an old allocation after a resolution or adapter switch, or you've got a physical GPU issue (less common on modern hardware, but it happens).

Cause 1: Driver corruption or version mismatch

What's actually happening here is the driver's internal state got out of sync. When you update a GPU driver without a clean install, leftover registry entries and old DLLs can point to allocations from the previous driver version. When a new allocation request comes in, Windows sees the old reference and says "that doesn't belong to this driver."

Fix: Clean DDU driver removal

1. Download Display Driver Uninstaller (DDU) from Guru3D. Don't skip this — regular uninstallers leave files behind.
2. Boot into Safe Mode (hold Shift while clicking Restart, then Troubleshoot > Advanced options > Startup Settings > Restart, then press 4 for Safe Mode).
3. Run DDU. Select your GPU vendor (NVIDIA, AMD, or Intel), then click "Clean and restart."
4. Once back in normal Windows, download the latest driver directly from your GPU vendor's site — not from Windows Update.
5. Install the driver with a Clean Installation option (NVIDIA has this under Custom install; AMD calls it Factory Reset).
6. Reboot and test the app that errored.

The reason step 3 works is DDU removes not just the driver but also driver store entries, registry keys, and leftover shader caches. A regular uninstall leaves those behind, which is exactly what causes the allocation mismatch.

Cause 2: App-specific allocation leak after resolution change

Some apps — especially older games or CAD software — create GPU allocations for a specific resolution or adapter. If you switch monitors, change display scaling, or unplug a secondary GPU (like an external Thunderbolt dock), the app doesn't release those old allocations. Next time it tries to render, Windows rejects the stale reference.

Fix: Reset the app's graphics state

1. Close the problematic app completely. Check Task Manager to make sure no background processes linger.
2. Open Graphics settings in Windows (Settings > System > Display > Graphics).
3. Find the app in the list. Click it, then Options, and set it to Power saving (integrated GPU) temporarily. Apply and close.
4. Open the same Graphics settings again, set it back to High performance (discrete GPU). Apply.
5. Launch the app again. This forces Windows to re-bind the allocation to the current device.

Skip the registry edits you might see online — they rarely help here. The Windows Graphics settings panel handles the GPU adapter binding for each app cleanly.

If the error persists, try this command in an admin PowerShell to clear the app's local cache:

Get-AppxPackage *appname* | Remove-AppxPackage

Replace appname with the app's package name (find it via Get-AppxPackage | Select Name, PackageFullName). Then reinstall the app from the Microsoft Store or its installer.

Cause 3: Hardware-level allocation corruption

This is rare but real. If your GPU has faulty VRAM — from overclocking, overheating, or manufacturing defects — it can return garbage addresses when the driver asks for a new allocation. The driver then tries to reference a non-existent block, and Windows flags it with 0XC0262115.

Fix: Test and stabilize your GPU

1. Run OCCT or FurMark for 10 minutes. Watch for visual artifacts or the error to reappear.
2. If you've overclocked (including factory OC from vendors), drop the memory clock by 200 MHz using MSI Afterburner or your vendor's tool. Test again.
3. Check GPU temperatures with HWMonitor. If VRAM temps exceed 95°C, clean your fans and reapply thermal pads.
4. If the error only happens under heavy load, your PSU might be failing. A dying PSU delivers unstable voltage to the GPU, causing allocation writes to land in wrong memory cells.

Don't bother with Windows Memory Diagnostic for VRAM — it only tests system RAM. Use Video Memory Stress Test (free tool) instead, which checks your GPU's VRAM banks directly.

Quick-reference summary

Start with Cause 1. It's the most common trigger by a wide margin — I've seen it on Windows 11 23H2 and 24H2 after driver updates from Game Ready drivers. Only move to hardware testing if the error follows you between different apps and persists after a clean driver install.