I've been having this troubleshooting issue ever since my ram memory card collapsed (I don't know what other ways to describe it but it died).
Some sites can't be reached and always tells me to:
Check if there is a typo in
www.roblox.com.
If spelling is correct, try running Windows Network Diagnostics.
While I did try to run windows network diagnostics, It opens up the troubleshoot but it doesn't work since it always says that an error occured while troubleshooting.