Fix ERROR_INSTALL_LOG_FAILURE 0x00000656

Quick answer for advanced users

Delete or rename the corrupted log file in %TEMP% named MSI*.LOG (wildcard). Run msiexec /unregister then msiexec /regserver as admin. That's it 90% of the time.

Why this happens

Windows Installer (msiexec) writes a log file every time you install or uninstall something. The log goes into the %TEMP% folder. When that file gets corrupted — usually from a crashed install, full disk, or weird antivirus locking — the next install attempt hits error 0x00000656. The error message says "Error opening installation log file." It's not a hardware failure. It's not a bad installer package. It's Windows tripping over its own log file.

I've seen this on Windows 10 21H2 through 11 23H2. It's most common after a failed Office or Visual C++ redistributable install. The culprit is almost always a stuck log handle from a previous session.

Clear the temp folder. Press Win + R, type %temp%, hit Enter. Select all files (Ctrl + A) and delete them. If any file says it's in use, skip it. Then empty Recycle Bin. Reboot.
Re-register the Windows Installer service. Open Command Prompt as Administrator. Run msiexec /unregister and then msiexec /regserver. This resets the service's internal state without reinstalling anything.
Check disk for corruption. Run chkdsk C: /f /r and let it schedule a scan on next boot. Reboot and let it run. This fixes bad sectors that might corrupt the log write.
Run SFC and DISM. In admin Command Prompt: sfc /scannow. After that finishes, run DISM /Online /Cleanup-Image /RestoreHealth. This repairs system files the installer depends on.
Clear the installer cache. Type %windir%\Installer in File Explorer. Sort by date, delete any .msi or .msp files older than a few days. Don't delete everything — you'll break Office patches. Just the recent ones.

Alternative fixes if the main steps fail

If the above doesn't work, check these specific cases:

Antivirus blocking — Temporarily disable real-time protection. I've seen Bitdefender and McAfee lock the log file handle. Try the install with AV off.
User profile corruption — Create a new local admin account and try the install from there. If it works, migrate your data.
Group Policy restrictions — Run gpresult /h gpresult.html and check for policies that restrict %TEMP% write access. Look under Computer Configuration > Administrative Templates > Windows Components > Windows Installer.
Third-party cleanup tools — CCleaner or similar can leave the temp folder in a locked state. Uninstall them, reboot, try again.

Prevention tip

Stop installs mid-way and you'll get this error next time. Always let failed installs fully roll back. Set a system restore point before major installs — that's your safety net. Also, keep at least 5GB free on the system drive. A full C: drive is the #2 cause after corrupted logs.

If it happens again, check the Event Viewer logs under Applications and Services Logs > Microsoft > Windows > Installer. Look for event ID 11728 — that's the exact log failure. The details will tell you which file path it's choking on.