How do I retrieve a Wi-Fi network that has been closed?

[AC Question]

I have a Samsung Tab Pro 10.1 (and a desk top PC) on which I received a message yesterday saying that the network was under threat and I should close down. Having promptly done this, I tried reconnecting later in the day. I went through the usual process of finding the network, entering the password and connecting. I was informed that the tablet was connected to the Wi-Fi but when I tried the internet, it immediately said there was no network connection. The internet on the PC was working perfectly so the problem related only to the tablet.
I have repeatedly tried to connect again but still the problem persists. I have tried the usual tactics of switching off the tablet and router (though if the PC is functioning, it cannot be a router problem), but still I find through I'm told the connection has been made, it is not available for any of the functions it is used for.
Has anyone got a solution, please?

 

[Rukbat]

It sounds as if you have a virus on your tab. Routers don't issue warnings like that. Remove the network from the tab ("forget" it). Then enter it again. As soon as you re-establish a connection, install an antivirus app and Malwarebytes Anti-Malware. Disconnect from wifi and run one app.. when it's finished, run the other one. Then you can connect to wifi again.