RN426E22 NAS Stuck on "Welcome to Netgear Storage" – No Button Response, No Network Access

One important point I missed earlier — there were frequent power failures on the day this issue started. The problem seems to have occurred after those outages

Here’s a summary of what I’ve done.

• I powered off the unit and removed all drives.
• When powering on the device using the rear switch only (without touching any buttons on the front panel), it still boots to the same screen: “NETGEAR Storage Welcome.”
• During startup, all four Ethernet port LEDs turn on briefly (just for a second).
• After that, when I plug in an Ethernet cable to any of the ports, the link/activity LEDs start blinking

All the above testing was done in disk-less mode (no drives installed).

​ ​  As suggested checked below  things too :(my observations as follows )

• How did you turn it on?  Did you have to press the power button, or did it just come on when plugged in?  

           I just plugged in the power cord, and after switching on the rear power switch, the unit powers on and reaches the 'Welcome' screen   — without pressing the front power button near the disk bays.

• When you turn it on, do you even see a flicker on the Ethernet LED?

            Yes

•   Do the drives spin up?

             Yes I can feel tiny vibration while touching the front portion of each disks and the blue light near to each 6 bays are ON only. ( for doing this step I kept all disks back ) 

•  You say you get no results from pressing any buttons.  Does that include a long press of the power button?

             While pressing unit goes off. 

Next Steps:

I’m planning to try the Memory Test option from the boot menu.

Can you please confirm:

Should I do the memory test with or without the drives inserted?

Will this process affect the existing RAID configuration or stored data in any way?

This storage was originally set up by someone else, and until now we’ve only accessed shared folders—no changes have ever been made to the admin settings.