Windows 10 update assistant stuck at 86%

Try Steps 3 and 4

FIX: Windows 10 Anniversary Update: Error 0x80070057

https://windowsinstructed.com/fix-windows-anniversary-update-error-0x80070057/

This computer is Windows 10 Pro with the Anniversary update installed.

Please provide a copy of your System Information file. To access your System Information file select the keyboard shortcut Win+R, type msinfo32 and click OK . Place the cursor on System Summary. Select File, Export and give the file a name noting where it is located. Click Save. Do not place the cursor within the body of the report before exporting the file. The system creates a new System Information file each time system information is accessed. You need to allow a minute or two for the file to be fully populated before exporting a copy. Please upload the file to your OneDrive, share with everyone and post a link here. If the report is in a language other than English, please state the language.

For help with OneDrive see paragraph 9.3:

http://www.gerryscomputertips.co.uk/MicrosoftCommunity1.htm

Please provide a copy of your System Information file. To access your System Information file select the keyboard shortcut Win+R, type msinfo32 and click OK . Place the cursor on System Summary. Select File, Export and give the file a name noting where it is located. Click Save. Do not place the cursor within the body of the report before exporting the file. The system creates a new System Information file each time system information is accessed. You need to allow a minute or two for the file to be fully populated before exporting a copy. Please upload the file to your OneDrive, share with everyone and post a link here. If the report is in a language other than English, please state the language.

For help with OneDrive see paragraph 9.3:

http://www.gerryscomputertips.co.uk/MicrosoftCommunity1.htm

Dear Sir,

Right now I tried updating my laptop to latest anniversary update through windows upgrade assistant. But sadly once again it is stuck to 86%. Please help. I have attached the system report:- https://1drv.ms/t/s!AotsgKRVjL4KhFYzpASBKvhRxJOz

https://1drv.ms/t/s!AotsgKRVjL4KhFa-NDtQigmG1A0M

Please help me to get my laptop to the latest build

When the windows upgrade assistant is struck at 86%, it continues forever. when i restart the computer and then once again start the windows upgrade assistant it remains forever at 0%. This is the new observation I have observed. If I delete the windows upgrade assistant application and reinstall it and then start afresh the download, once again it remains struck at 86%.

Please help.

I am not understanding why it is happening.

Do you have some wireless mouse or keyboard? Remove those nano receiver from the laptop or desktop and reboot Windows. Also remove any USB device for this installation duration.