Does your PC have a LAN cable connection? If so, just connect this to the DNS or the main host router and be sure the DNS is connected to the main host router as well.
Start at step 3 -
Update procedure:
1) Backup the configuration to a file and store it on something like a usb stick, assuming you are satisfied with the configuration as it is. (updating the firmware returns the unit to factory state).
2) Make sure you have a validated backup of your data. (we haven't encountered any problems but it is better to be safe than sorry).
3) Check the downloaded zip file and then unzip it to a known location on your PC.
4) Open the web UI of your nas and go to the 'firmware' page (usually under 'tools')
5) Use the 'browse' button to locate the firmware on your PC and select the unzipped file.
6) Click on 'open' then click on 'apply'. (this will copy the firmware to the nas and do the upgrade)
7) MAKE SURE THE UNIT STAYS ON UNTIL THE UI RETURNS AFTER YOU CLICK 'continue'.
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Use the UI to confirm the firmware has been updated.