Windows error
Windows error 0x80070005
Access denied. A permission, policy, or security tool blocked a file or service Windows Update or an installer needed.
What this error means
0x80070005 means "access denied." Something ran without permission, or a folder is locked. It is not automatically malware, and it is not a reason to take ownership of C:\Windows.
Common causes
- Not running an installer as administrator when it requires it
- A work policy blocking the action
- Antivirus locking files during an update (sometimes)
- A damaged user profile
Safe fixes
Use an administrator account the right way
Right-click the installer → Run as administrator if you trust the source (vendor site or Microsoft). If you are not an administrator on the PC, you cannot override this, ask the owner or IT.
Do not disable Windows Security as a first experiment
Temporarily adding an exclusion is still a security decision. Prefer retrying the update after a restart. If a work antivirus is present, ask IT instead of fighting it.
Advanced fixes
Avoid taking ownership of system folders
Forum steps that "take ownership of System32" create lasting security holes. Skip them. Use DISM/SFC or a repair install if Windows files are the problem.
When hardware may be involved
Permissions errors are software and policy. Hardware is unrelated unless the disk is failing and files are unreadable, that usually looks like disk errors, not 0x80070005 alone.
When to get professional help
Work devices and school PCs often throw this on purpose. Contact the administrator. For a home admin account that still cannot update, a repair from official media may be cleaner than permission surgery.