ReadyNAS NV+ RND4410 | Doesn't boot up after swapped disk

Hi

I have searched but haven't find any solutions in the forum on this problem.

I have a Netgear ReadyNAS NV+ (RND4410) that we bought 5,5 years agao.

It has worked well and contains four 1TB-disks.

Two weeks agao I was about to change all disks to 2Tb-disks as I read that it supported that.

As it's a X-Raid NAS I just pulled the disk from slot 1 and mounted the first new 2tb disk
I got the new entries in the web-interface-log that the disk had been pulled and that the new disk had been mounted and it started the sync (LED blinking on slot 1).

After a while I couldent reach the web-interface and I thought that it was because the sync was in progress so I left it alone.

But after the weekend (3 days later) it still said syncing and I could still not reach the web-interface.

I pulled the plug and rebooted the NAS.

It did a check on the NAS volume I think and then it said booting with the LED on slot 1 still blinking.

I have now waited another 30 hours and still the same thing. Stuck on Booting and can not reach it in the web-interface.

Not even the RAIDar program finds it.

I can ping the IP though.

What to do now??

Thanks for all help!
The information on this disk is very important.

/David