Did you get this error when you try to use the Windows Explorer in your SharePoint site to upload or download files?
You're in luck because I already searched the solution to this error.
Here's how to fix this error:
1. Check your WebClient service if it is started. If you don't know how to start, stop or restart services go to your Control Panel, Administration, then Services. Browse to see the WebClient.
2. Add your SharePoint Team Site to the "Trusted Sites" location of the browser. In your Internet Explorer, click the Internet Options, click the Security tab, then Trusted site, here you can add your team site. You can use the fully qualified domain name or IP address e.g. 192.168.4.100 as example.
3. Clear the browser cache. Actually, I did not clear my browser cache and it works for me.
Check it out.
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