It was necessary to flash TP-Link TL-WR841N router, because it periodically hung up, disconnected from the Internet, the router itself was pinging at that moment, but it was impossible to enter its web interface.
First, check the hardware version of the device, usually it is indicated on the label under the router, in our case it’s V8. I note that updating the firmware not from that version of the device can spoil it! Also, you can not update the firmware on Wi-Fi and turn off the power of the router during the firmware!
And so, to update the firmware you need:
1) Download the archive with the new firmware from the official site and unpack it
https://www.tp-link.com/us/download/TL-WR841N.html
2) Open the router settings by typing in the browser address http://192.168.0.1 and enter your login – admin, password – admin.
3) In the menu choose System Tools -> Firmware Upgrade, click the “Browse” button, select the previously downloaded firmware. Click “Upgrade”. Wait for the firmware to be installed and the device will reboot automatically.
After updating the firmware, the settings in the router are reset to standard.
Done.
This router model also has unofficial firmware DD-WRT
http://www.dd-wrt.com/site/support/router-database