By the way, that is 99% chance a DNS server problem (If it is not a browser hijack). If it happens again, try manually entering the DNS server from your ISP or another company.
What is happening is your services that connect via IP addresses still work fine, like Messenger and such, but when you need to resolve a name to an IP address, your inability to talk to a DNS server means your computer goes 'huh'?
Is that a good way to explain it?
If worst comes to worst, simply leave your DNS servers entered manually under the hosts adapters TCP/IP settings.
-S
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