WDBBCL0040JBK-NESN compatibility with 8tb hd

I’m new to working with nas. I purchased a pr2100 (WDBBCL0040JBK-NESN) for file storage and to act as a plex server. I’m still struggling with Plex, but today my priority is upgrading my drives from 2x 2tb drives to 2x 8tb drives. When I load my WD Red 8tb drives I get nothing but 2 red lights. WD dash won’t load. Any assistance is appreciated.

How did you configure the 2x 2TB? JBOD or RAID1?
Are you able to boot and get the web interface without any disks?

In case you had RAID1 (mirror mode, 2TB capacity), you should upgrade only 1 disk at once.

Tfl, thank you for your response. NAS was originally configured to Raid 1. I’ve tried loading 1 8tb in with the 2tb. I get nothing but a red light. Disk status says disk is bad, but it is brand new.