Try downloading the firmware file again. Ensure you have the J1 file.
The typically features a different Wi-Fi chipset and flash layout compared to older revisions. Using firmware intended for the H/W Ver A1 or B1 on a J1 unit will result in:
Avoid “firmware download aggregator” sites that ask for your email. They often bundle malware. Only download from manufacturer domains or trusted open-source repositories. d-link dsl-2750u h w ver j1 firmware
After the update, it is recommended to reset the router to factory settings to avoid any configuration conflicts.
1x RJ-11 DSL port, 4x RJ-45 10/100 Ethernet LAN ports, 1x USB 2.0 host Try downloading the firmware file again
Note down the current (Firmware Version) listed next to it to track your upgrade progress. 3. Where to Safely Download DSL-2750U H/W Ver J1 Firmware
The router will take a few minutes to upload the file, flash the memory, and reboot. Using firmware intended for the H/W Ver A1
Always match the firmware to the exact Hardware Version (H/W Ver).
You can also search the official D-Link FTP repository for your region. A widely used archive is the Russian support site at https://support.d-link.ru/pub/ADSL/DSL-2750U/Firmware/ . It contains various firmware versions, but you must navigate carefully and ensure any file you download explicitly states it is compatible with the J1 hardware revision.