Tablet wont connect to internet

The make and model of the tablet is the important bit missing in this question. There may be a security setting to 'Enable Hotspots' as they can be a security issue allowing access to the device.

Google

make model enable wifi hotspots

try to look on youtube on this should be easy to set up , just goto setting and internet options etc ,

I've known some tablets not connect to the standard 2.4G wifi but are quite happy on the newer 5G wifi. don't know why.
I've also known some tablets only connect to WEP security or none.
see if you can change the security settings in your router.

Go to your settings, to about device or to back up and reset, try unplugging your internet modem and plugging it back in that usualy helps.

Need To Double Check Password And Connection Info. One Error Sets The Whole Thing Off As Wrong.

look for proxy in the internet settings.

I was told if you have more than one wireless connection available it will not work right.
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False. You can only connect to one network at a time. The "security certficate..." is due to another error. You don't need SD card to download things - the tablet has some memory of it's own.
Define more clearly your problem.

Hi there. I noticed that sometimes Android devices seem to have trouble connecting to certain access points or.they seem to stop connecting alltoghether to certain routers. Sometimes this method can help: Select the network you are trying to connect to and select "forget this network". Reboot the tablet and try to reconnect again. Sometimes this doesn't work on the first try. If that doesn't work I have heard of other fixes but they require "rooting" the tablet which could be potentiall dangerous. Another thing you can try if that doesn't work is change the security to a different encryption type. Your password will either be WEP or WPA. Whatever it is try to change it to the other. I cannot give you detailed instructions on this because I don't know your router model or its current settings. Hopefully this helps and leave a comment if you have further questions. Good luck!

Try connecting to the Internet through the ethernet port (via a cable). If Internet Explorer loads the target page then you have a configuration problem with WI-Fi access : The wireless security settings are not allowing the computer to access the Internet.
If Internet Explorer does not connect with the cable then the problem resides with Internet Explorer. Try to reset the defaults. To confirm that download FireFox and use it. Besides you need two browsers just in case one acts up.

how connect samsung BD-P160 blu ray to internet
I am connected to netword, you tube..