I cannot access the internet through my router after installing update, but I can at different locations
That shows there's something wrong with your router and not your iPad.
MY router works perfectly well with my wife's ipad and my desktop computer.
Your iPad also works perfectly on other router.
So even if your wife iPad is working doesn't mean your router is configured property.
iOS: Troubleshooting Wi-Fi networks and connections
Turn of router for 30 seconds and turn off ipad wait for router to reboot
then turn ipad back on if it still will not work on ipad on the network on ipad
click on forget this network then type in the wireless key for your router
and try to connect to internet.
Although it helped, it did not unfortunately solve the problem. I don't believe there is a problem with the router and I think it can only be the update as after that it all went wrong.
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