Search for your model on the D-Link Global Support or D-Link India Support pages.
If everything works fine, a firmware update may not be necessary. dsl2520uz2 firmware free
The process takes roughly 2–3 minutes. Do not unplug the power during this time. Search for your model on the D-Link Global
D-Link maintains open FTP servers and support portals where firmware can be safely downloaded for free: Russian/European D-Link FTP Portal: You can access archived and active firmwares via the D-Link /pub/ADSL Directory dsl2520uz2 firmware free