Windows activation error 0xC004C020: Volume license used on too many devices
Updated
Cleared for publishing after the automated checks on .
What the code means
The activation server reported that the Multiple Activation Key has exceeded its limit. (Troubleshoot Windows activation error codes)
Code facts for 0xC004C020
| Code as Windows shows it | 0xC004C020 |
|---|---|
| Type | Activation error code |
| Hexadecimal, 8 digits | 0xC004C020 |
| Decimal (unsigned) | 3221536800 |
| Decimal (signed 32-bit) | -1073430496 |
| Group | Activation errors |
Read with care
- Not a standard HRESULT (R bit set without the N bit, MS-ERREF 2.1). Microsoft lists it as a Windows activation (Software Protection) code; do not split it into facility and error number. ([MS-ERREF]: HRESULT, Troubleshoot Windows activation error codes)
Code facts: Troubleshoot Windows activation error codes (Microsoft Learn, CC BY 4.0), checked Nov 14, 2026.
Where this error shows up
This code shows up when Windows tries to activate or when the product key is checked.
Applies to
Windows 11 and Windows 10 (activation help page); volume activation page applies to supported Windows Server versions and is written for IT professionals.
Try these first
These steps carry no risk flag in the data. They keep the order of the full list below, which is not reordered. A step without a flag is not a promise that it is safe for your computer.
2 steps to try, in order
Steps are grouped by the Microsoft page they come from. The page lists only what those pages give; other causes of 0xC004C020 are not covered.
If this page and Microsoft's page differ, follow Microsoft's page.
From: Get help with Windows activation errors
Source: Get help with Windows activation errors (Microsoft Support), checked Nov 14, 2026. Summary in our own words; Microsoft's page has the full steps.
Steps follow the Windows 11 tab of Microsoft's activation help page; its Windows 10 tab has its own version of this row (Windows 10 support ended on October 14, 2025).
Ask your organization
You may need a different product key for this device; your organization's support person can tell you more.
From: Troubleshoot Windows activation error codes
Source: Troubleshoot Windows activation error codes (Microsoft Learn), checked Nov 14, 2026. © Microsoft, licensed under CC BY 4.0. Steps shortened and reworded by PC Driver Update.
Microsoft's volume activation (MAK/KMS) error page, written for technical support agents and IT professionals.
Request more activations
Written for IT administrators.
By design a MAK can be activated only a limited number of times. Request more activations to increase the limit by contacting the Microsoft Licensing Activation Centers.
Stop and get help
If these steps do not fix the problem, or you are not sure about a step, stop and get help from Microsoft Support or from the maker of your PC. Stop at once if the data on this computer is at risk: back up your files first, or ask a professional before you go on.
Dates and review
| Automated checks | first check: ; fourth check: |
|---|---|
| Microsoft pages read |
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| Review status | Cleared for publishing after the automated checks on . |