How to resolve error code 0x800705b4: Windows Update encountered an unknown error in Windows Server 2008 R2

To resolve error code 0x800705b4 in Windows Server 2008 R2, follow these steps:

1. Restart your computer: A simple restart may resolve the issue. Restart and attempt the update again.
2. Check your internet connection: Ensure your internet connection is stable. For wireless connections, try using an Ethernet cable to connect directly to the router.
3. Disable antivirus software: Antivirus programs can sometimes interfere with updates. Temporarily disable your antivirus and retry the update.
4. Run Windows Update troubleshooter: Utilize the built-in troubleshooter to address update problems. Navigate to Control Panel > Troubleshooting > System and Security > Fix problems with Windows Update.
5. Reset Windows Update components: If troubleshooting fails, reset the Windows Update components. Open Command Prompt as an administrator and run these commands:

net stop wuauserv
net stop cryptSvc
net stop bits
net stop msiserver
ren C:\Windows\SoftwareDistribution SoftwareDistribution.old
ren C:\Windows\System32\catroot2 catroot2.old
net start wuauserv
net start cryptSvc
net start bits
net start msiserver

6. Install updates manually: If all else fails, download and install updates manually from the Microsoft Update Catalog.