Backup "The device is not ready"" error

I’m using Windows Backup to backup files form my PC to a share on the EX2100. After the backup has been running for a while, it fails with the following error: “The device is not ready”

This is the 3rd time I’m experiencing this failure, trying to perform the same backup. I’ve checked the EX2100 and it shows healthy; the windows share is accessible. On this last run I saw the notification area showing a network link down error, but that happened about 7-minutes AFTER the backup failed:

Any Idea what might be causing this problem? or how to fix it?

Thanks

Hello, do you have a static IP on the drive? Is your computer wired or wireless? What kind of router do you have?

I didn’t change any of the default configuration on the NAS EX2100, so it looks like it’s setup as DHCP IP. Also the network is wired (network cable). The router is a Netgear RangeMax 240 Wireless router.
Thanks