Updating the firmware on your D-Link 2750U router is essential for several reasons:
Before proceeding, note that there are multiple hardware versions of the DSL-2750U (e.g., Version T1, Version U1, etc.). Installing the wrong firmware version can render your router unusable. dlink 2750u firmware update
After a firmware update, the router may revert to factory default settings. Updating the firmware on your D-Link 2750U router