Windows Update Error 0x800700B7 — What It Means & How to Fix It

What Does This Error Mean?

Windows Update error 0x800700B7 means 'Cannot create a file when that file already exists.' Windows tried to create a new update file, but a file with the same name was already there — usually left behind from a previous failed update attempt. Clearing the Windows Update cache almost always fixes this immediately.

Affected Models

Windows 10
Windows 11
Windows 8.1

Common Causes

A previous update attempt failed halfway, leaving partial or locked files in the update cache
The Windows Update temporary files folder contains leftover files from a prior interrupted installation
A system backup or shadow copy tool is locking update files and preventing Windows from replacing them
Antivirus software quarantined or locked an update file that Windows is now trying to recreate
A corrupted update transaction log is replaying a file creation that already completed

How to Fix It

Clear the Windows Update download cache. Open Command Prompt as Administrator. Type these commands one at a time, pressing Enter after each: net stop wuauserv — net stop bits — net stop cryptsvc — then type: rd /s /q C:\Windows\SoftwareDistribution — then restart the services: net start wuauserv and net start bits and net start cryptsvc.

This is the most effective fix for 0x800700B7. The SoftwareDistribution folder holds all downloaded update files. Windows recreates the folder automatically when the services restart, with no leftover conflicting files.
Run the Windows Update Troubleshooter. Go to Settings > System > Troubleshoot > Other troubleshooters > Windows Update > Run. This automates the cache clearing and service reset process and checks for other common blocking issues.

The troubleshooter is the easiest starting point. It handles the same steps as manual cache clearing in a guided, automated way.
Also clear the catroot2 folder. In Administrator Command Prompt, type: net stop cryptsvc — then: rd /s /q C:\Windows\System32\catroot2 — then: net start cryptsvc. This folder holds update signature verification data and can also accumulate conflicting files.

The catroot2 folder is rebuilt automatically when cryptsvc restarts. Clearing it alongside SoftwareDistribution gives the update process a completely fresh start.
Temporarily disable your antivirus before updating. Open your antivirus program and look for a 'Disable protection' or 'Pause' option. Set it to pause for 30 minutes. Run Windows Update. Re-enable antivirus immediately after the update finishes or fails.

Antivirus programs sometimes intercept update file writes and flag them as suspicious. Temporarily disabling during the update process lets Windows write files without interference.
Restart the Background Intelligent Transfer Service (BITS). Open Command Prompt as Administrator and type: net stop bits — press Enter — then: net start bits — press Enter. BITS is what downloads Windows Update files in the background — restarting it clears any stuck download state.

BITS keeps track of what it has downloaded. If that tracking information is corrupted or references a file that no longer exists, you get the 'file already exists' conflict. Restarting BITS clears this state.

When to Call a Professional

This error almost always resolves with a cache reset. If it persists after all troubleshooting steps, a technician can use advanced Windows Update diagnostic logs to find which specific file is blocked.

Frequently Asked Questions

Is it safe to delete the SoftwareDistribution folder?

Yes, completely safe. The SoftwareDistribution folder contains only downloaded update files and metadata — no system files, no personal files. Deleting it simply forces Windows to re-download any updates it needs. Windows automatically recreates the folder and its contents the next time the Windows Update service runs. You may need to re-download recent updates, but they will install fresh without conflicts.

The error comes back every time I update. Why?

If the error keeps returning, something is consistently interfering with update file creation. The most likely causes are antivirus software that keeps quarantining update files, or a backup/VSS (Volume Shadow Copy) tool that keeps locking them. Check your antivirus quarantine log for any Windows Update related files. Also check if automatic backups are scheduled at the same time as updates — reschedule one of them.

Can I manually install the update instead?

Yes — visit catalog.update.microsoft.com and search for the KB number of the failed update. Download the standalone installer and run it directly. This bypasses the Windows Update service entirely, which avoids the file creation conflict. This is a reliable workaround if the automatic update keeps failing.