Windows update error code 643 is troubling many users at the time of installing Windows updates. As a result, this error prevents Windows from updating. This error is more frequent on Windows 7, 8, and 8.1 PC. There is no doubt that this error can stem from a number of issues like a conflict with security software, malware infection or corruption in Windows Registry. Apart from this, the older version of drivers, recent system changes, and many other factors can cause this issue.
Probable Methods to Fix Windows Update Error Code 643:
Here are a few solutions for how to fix Windows update error code 643 permanently from your PC.
Method 1: Run Windows Update Troubleshooter
This inbuilt tool of Windows has often solved many issues successfully. Thus, use these tools before applying any other solutions.
- If your Windows does not contain this tool, then search for it on the internet.
- Click Windows Update Troubleshooter and then tap on the ‘Save File’ option next to it.
- Select a location to save the file, click the ‘OK’ button to download the file.
- After finishing the download, go to the location where you have downloaded this tool.
- Now, double-click on the tool in order to launch it on your PC.
- On the Windows Update Troubleshooter window, click on the ‘Advanced’ tab.
- Select ‘Apply repairs automatically’ option and tap ‘Windows Update.’
- Then, press the ‘Next’ button and follow the on-screen instructions to run the troubleshooter.
Method 2: Turn Off Antivirus Software
Most third-party antivirus software seems to conflict with Windows update and lead to Windows update error code 643. Thus we would ask you to temporarily disable the antivirus and check whether it fixes the problem or not. Then you will come to realize whether it was causing this issue or not. Follow these steps in order to disable the antivirus.
- Go to the Start menu and search for the Control Panel.
- Select Control Panel(Admin) and click on ‘Programs.’
- Then, click the ‘Uninstall a program’ link and find out the antivirus that you want to remove.
- Right-click on the program and choose ‘Uninstall’ option.
- Click ‘Yes’ on the resulting popup to confirm this action.
- Wait for Windows to display a confirmation message for the successful uninstallation of the program.
Alternatively, you can follow the shortcut, mentioned below to uninstall the antivirus software.
Press the Windows logo key and ‘X’ to open the Main menu. Select Task Manager and click the ‘Startup’ tab on the Task Manager window. Choose your antivirus and tap the ‘Disable’ button at the end of the window. After removing the program from running at the system startup, try to install Windows update. Proceed to the next solution if the update fails.
Method 3: Uninstall ‘.Net Framework 4 Client Profile’
We have found this solution to be effective for fixing Windows update error. Here is how to uninstall a corrupted ‘.Net Framework 4 Client Profile.’
- Open Control Panel from the Start menu and choose ‘Programs and Features’
- Select ‘Microsoft.Net Framework 4 Client Profile’ and tap the ‘Uninstall’ button at the end of the screen.
- Restart the PC and see whether you can install the Windows update or not.
Method 4: Repair NET Framework Client Profile Using Control Panel
The Control Panel contains the installed NET Framework version in Windows that you can repair by the following way:
- Press Windows logo key and ‘R’ at the same time to launch the Run application.
- Type ‘appwiz.cpl’ in the Run dialog box and press ‘Enter’ or click the ‘OK’ button.
- Now, go to the ‘Programs and Search’ box and enter ‘NET Framework’ in it.
- Locate the latest NET Framework Client Profile and double-click on it to open the maintenance window.
- Choose the ‘Repair’ option and tap the ‘Next’ to start repairing task.
- Hit the ‘Finish’ button once the repair is done and restart the PC to let the changes take effect.
- Now, you will be able to update Windows if this solution has worked for you.
Method 5: Reinstall Microsoft NET Framework
If the Windows update error code 643 persists even after repairing the NET Framework, then reinstall this framework.
- To do so, open a browser and visit Microsoft’s page.
- Click the ‘Download’ button next to the ‘NET Framework Setup Cleanup Utility ZIP.’
- After downloading the utility, go to File Explorer and open it.
- Then, tap the ‘Extract all’ button and choose the ‘Browse’ option.
- Select a path for the extracted NET Framework Setup Cleanup Utility ZIP and click the ‘Extract’ button below.
- It opens the utility ZIP from the extracted folder.
- Click ‘Net Framework’ and select ‘All Versions’ from its drop-down menu.
- Tap the ‘Cleanup Now’ button and reinstall the NET Framework from the Microsoft NET Framework download website.
- Restart the system and try to update Windows.
Method 6: Scan your PC for Malicious Programs
Windows update error code 643 can be a sign of malware or virus affected PC. Thus, you have to scan your PC in order to remove such unwanted programs from it as soon as possible.
- So, download a reliable antivirus or antimalware if your PC does not have one.
- Then, run the software and let it scan the system.
- If it traces any signs of malicious program, then the scanning result will display the same.
- Then, you will need to wait until the security software eliminates such malicious programs from your PC.
Method 7: Update the Network Adapter Driver via Device Manager
The network adapter driver installed on your PC might be out-of-date and hence causing update issues. Therefore, you will need to update it to its latest version and check whether it fixes the problem or not.
- Click the Start menu and right-click on the ‘Computer’ icon.
- Choose ‘Manage’ from the list of available options to access the ‘Computer Management’ screen.
- Select Device Manager and search for your network adapter from the list of installed devices.
- Right-click on the network adapter and select ‘Update its driver software.’
- After the update is completed, try to install the Windows update.
Method 8: Reset Windows Update Components
- Press Window logo key and ‘R’ to open the Run dialog box.
- Type ‘cmd’ in it and press ‘Enter’ to launch Command Prompt.
- Then, select ‘Run Command Prompt as administrator’ and type the commands coming up on the screen
- Press ‘Enter’ after typing each command in order to execute it.
- After executing all commands, close the Command Prompt window.
- Restart the system and ensure that you are able to update Windows.
Method 9: Fix Windows Registry
If a virus or malware enter your PC, then it might modify or corrupt one or more Windows Registry entries. As a result, it leads to undesirable effects and interrupts the Windows update. It is an extremely risky affair to repair the Registry coming. Moreover, it might erase the data stored on your PC. Thus, we would recommend to create a backup and fix the Registry by a special tool. We have discussed the whole process in the listed below steps:
- Go to the Start menu, type ‘command’ in the search bar but do not press ‘Enter.’
- Now, hold both the ‘Ctrl and Shift’ keys and hit ‘Enter’ on the keyboard.
- If a permission box appears, then click on ‘OK’ to continue.
- Type ‘regedit’ in the resulting popup and press ‘Enter.’
- On the Registry Editor, select error code 643 related key and choose ‘Export’ under the ‘File’ menu.
- Go to the ‘Save In’ list and select a folder for saving the Windows update backup key.
- Navigate to the ‘File Name’ box and more net a name for the backup file and click the ‘Save’ button.
- After that, move to the ‘Export Range’ box and make sure that the ‘Selected branch’ is selected.
- Tap the ‘Save’ button to save a backup of the Windows Update Registry entry with a ‘.reg file extension.
- Repeat the above steps if there is more than one affected Registry entry.
- Now, visit Microsoft’s website and download a tool for editing the Windows Registry.
- Install the tool on your PC and run it to fix the corrupted Windows Registry entry.
Method 10: Restore the System to a Previous State
A system restore is a proven method for solving many critical system issues. If Windows update error code 643 is appearing after a recent system change, then a system restore can help you. So, follow the instructions below to undo recent system changes and restore the Operating System.
- Go to the Start menu, type ‘System Restore’ in the search box and press ‘Enter.’
- On the ‘System Restore’ window, click the ‘Restore system files and settings’ link.
- Tap the ‘Next’ button and select a most recent restore point when your PC was working fine.
- Click ‘OK’ to confirm the restore point and the system will automatically restart after the restore point is created.
This article has provided you with solutions that are sufficient enough to fix Windows update error code 643. For any queries or technical assistance, give your feedback in the comment section below.