Fix 0XC01E05E6: Graphics Parameter Array Too Small

First Cause: Corrupt or outdated display driver

This is the one I see most often. The error 0XC01E05E6 pops up when a DirectX application tries to send a graphics parameter array to the GPU, and the driver tells Windows the array is too small. In plain English: the driver is either buggy or doesn't match what the app expects. Had a client last month whose entire print queue died because of this — no, actually that was a different machine. But about two months ago, a small architecture firm called me because their CAD software kept crashing with this exact code on their Windows 10 Dell Precision workstations.

The fix? Update or roll back the driver. Don't trust Windows Update for this. Go straight to the GPU manufacturer's site — NVIDIA, AMD, or Intel. Download the latest driver for your exact card model and Windows version. If you just updated and the error started, roll back instead. Here's the process:

1. Open Device Manager (Win + X, then choose Device Manager).
2. Expand Display adapters, right-click your GPU, and select Properties.
3. Go to the Driver tab. If you want to roll back, click Roll Back Driver. If you want to update, click Update Driver and browse to the file you downloaded.
4. Reboot. Do not skip this. I've seen the error persist until a full restart.

If that doesn't work, use Display Driver Uninstaller (DDU) in Safe Mode to completely nuke the old driver. Then install fresh. DDU is free and it's the only way to be sure every trace is gone. I've fixed dozens of machines this way.

Second Cause: DirectX runtime corruption or mismatch

Sometimes the driver is fine, but the DirectX files themselves are junk. This happens more on Windows 10 and 11 after failed updates or when you've installed a game that bundles an older version of DirectX. The error 0XC01E05E6 can pop up because the application expects a certain array size that the installed DirectX runtime doesn't support.

Fix: Run the DirectX End-User Runtime Web Installer from Microsoft. It's a small download that checks what you have and fixes what's missing. Also run the System File Checker. Open Command Prompt as admin (right-click Start, choose Command Prompt (Admin) or Terminal (Admin)). Run:

sfc /scannow

Let it finish. Then run DISM to fix the component store:

DISM /Online /Cleanup-Image /RestoreHealth

Reboot after both. Had a client whose business accounting software kept crashing with this error. Turns out a Windows update had nuked his DirectX 11 runtime. This fixed it in ten minutes.

Third Cause: Memory or hardware instability in the GPU subsystem

Less common, but I've seen it. The error means the array the GPU expects is smaller than what the driver sent. That can happen if the GPU memory controller is flaky, or if the PCIe link between the GPU and motherboard has errors. Usually shows up after a system crash, power outage, or if you just installed a new GPU.

First, reseat the GPU. Power down, unplug, open the case, take the card out, and reinsert it firmly. Make sure the PCIe power cables are clicked in. I once had a server that threw this error every other day — turned out the GPU was half-unseated from a cable tug.

If that doesn't work, test the GPU in another machine if possible. If it fails there too, the card is bad. Also check your PSU. Underpowered or failing power supplies cause all sorts of weird GPU errors, including this one. Use a tool like OCCT to stress test the GPU and watch for voltage drops.

Finally, update your motherboard's BIOS and chipset drivers. A BIOS update can fix PCIe compatibility issues that cause parameter array mismatches. Had a client with an AMD Ryzen build running a NVIDIA card — a BIOS update from the board vendor fixed his random 0XC01E05E6 crashes.

Most people fix this with the first cause. But if you're still stuck, work through each one in order. Don't skip the reboot after each step. And if you're on a laptop, make sure you're using the discrete GPU driver, not the integrated Intel one — that mismatch can also trigger this array error. Good luck.