You can try to open the 'services.msc ' (Win+R) , and close the 'Windows Update'.
Then type 'net stop WuAUServ' in cmd to close Update Service.
Find the 'SoftwareDistribution' folder in 'C:\Windows' and rename it as 'SDold'.
Finally restart the update, uninstall the .net framework and install it again.
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We can't locate the exact problem by viewing a picture without any detailed error messages, but I gave you two links to help you solving this problem, hope they can help you