Fix ERROR_REGISTRY_QUOTA_LIMIT 0X00000265 on Windows

You're in the middle of saving a file or installing a program, and out of nowhere you get the error ERROR_REGISTRY_QUOTA_LIMIT (0X00000265). This usually pops up when the system registry runs out of allocated space. I've seen it happen on Windows 10 and 11, often when someone is working with a large application like Adobe Photoshop or a database tool that writes a lot of settings. The registry has a hard cap, and once you hit it, nothing new can be written.

Why does this happen?

The registry is a database that stores configuration data for Windows and your apps. It's stored in memory and on disk, but Windows limits the total size of the registry to prevent it from growing endlessly. That limit is called the “registry quota.” By default, it's a percentage of the system's memory, but it can be exhausted if you have many programs, especially ones that write a lot of temporary keys.

Over time, leftover entries from uninstalled software, badly coded apps, or even malware can bloat the registry. When the quota is used up, any attempt to write to the registry fails, and you see error 0X00000265. This is more common on systems with less RAM because the quota scales with memory.

You might also see this error when a single process tries to write a huge amount of data at once. For example, a custom application that stores user preferences in the registry can hit the limit during a save operation.

First things first: free up some space

The quickest fix is to clean out the junk. Here's what I'd do before touching any settings:

1. Open Disk Cleanup by typing cleanmgr in the Start menu and hitting Enter.
2. Select your system drive (usually C:) and click OK.
3. After the scan, click “Clean up system files” at the bottom. This reruns the scan with deeper options.
4. Check all boxes, especially “Temporary files” and “Thumbnails,” then click OK. Wait for it to finish.

That frees up disk space, which doesn't directly affect the registry quota, but it's good hygiene. The real issue is registry bloat, so you need to prune it.

Clean the registry safely

Skip those third-party “registry cleaner” tools. They rarely help and can break things. Do it manually with the built-in tools.

1. Press Win + R, type regedit, and press Enter.
2. Back up the registry first: File > Export, choose a location, and select “All” under Export range. This saves everything in case something goes wrong.
3. Navigate to the two main uninstall keys:

   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall

   HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall

4. Look for entries that reference programs you've already uninstalled. They might have names that don't match anything installed. If you're unsure, right-click and export a single key first.
5. Delete those leftover keys. Right-click > Delete.

This alone won't always solve the problem, but it's a start. If the error continues, you need to raise the quota.

Increase the registry quota

Windows doesn't let you set an unlimited quota, but you can raise the limit. There are two ways: via Registry Editor or Group Policy. The Group Policy method is cleaner and applies to the whole system.

Method 1: Registry Editor (works on all editions)

1. In RegEdit, go to:

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control

2. Look for a DWORD value named RegistrySizeLimit. If it doesn't exist, right-click on the Control key, select New > DWORD (32-bit) Value, and name it RegistrySizeLimit.
3. Double-click on it, select Decimal, and enter a value in bytes. For example, 4294967295 (which is the maximum) or something like 2147483648 for 2 GB. The default is usually a fraction of RAM, so setting 2 GB is safe for most systems.
4. Click OK and restart your computer.

After restarting, the new quota applies. You can check the current limit by opening Task Manager, going to Performance > Memory, and looking at “Commit charge” — not exactly the registry, but it gives you a rough idea.

Method 2: Group Policy (Windows Pro or Enterprise)

1. Press Win + R, type gpedit.msc, and press Enter.
2. Navigate to Computer Configuration > Administrative Templates > System > Registry.
3. Double-click on “Prevent the registry from being backed up” — wait, that's not it. The real policy is “Registry Size Limit” under the same folder.
4. Set it to Enabled, then enter a size in MB. I'd suggest 2048 MB for a 4 GB RAM system, or 4096 MB if you have 8 GB or more. Don't go crazy; too large can cause boot issues.
5. Click Apply and OK, then restart.

Both methods achieve the same thing, but Group Policy is more reliable because it's a supported mechanism.

What if it still fails?

If the error persists after cleaning and raising the quota, there's a deeper problem. Check for malware that might be flooding the registry. Run a full scan with Windows Defender or Malwarebytes.

Also, look at specific applications that might be misbehaving. If the error appears when you use a particular program, try reinstalling that program. Sometimes a buggy app writes an excessive number of keys, and reinstalling resets its own registry usage.

If it's happening during Windows Update, you might have a corrupted update cache. Run sfc /scannow in an elevated command prompt, then DISM /Online /Cleanup-Image /RestoreHealth. Reboot and try again.

In rare cases, the registry hive itself is corrupted. That's when you need a system restore point or a repair install. But that's the nuclear option. Try the steps above first, and I'm confident you'll get past that error.