: Check the sticker on the bottom of your router. It must say H/W Ver: V2 . Do not use firmware for Rev C, T, or U1/U2 on a V2 device.
Some reviewers mention that if the modem is used for more than 24-48 hours continuously, a manual restart might be needed to maintain peak performance. Safe Upgrade Checklist dlink dsl2750u v2 latest firmware update link
Click , select the .bin or .img file you downloaded, and click Upload . : Check the sticker on the bottom of your router