Windows Backup Fail on 4TB array

[lmaximo]

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Hi to all and sorry for my English,

I hope to be in correct forum section.

Windows 2008 R2 on MicroServer PS HP ProLiant N40L 658553-421

We have 2 HDD of 500GB in RAID 1 used as boot array.

Some day ago, we add 2 HDD WD40EFRX-68WT0N0 in RAID 1 to use as Windows backup destination for another server on lan.
RAID 1 of 4TB as recognized and configured as Base GPT and formatted as NTFS.

Issue: When we run Windows Backup from other server on lan, with destination in a share of this 4 TB array, jobs fails and we receive error (translate from italian): Unable to create backup file. Unable to execute the request because I/O device error. if we move backup destination on share in 500GB Array all work fine.

This happened also if we (for test) run Windows Backup locally.

Nothing change if we install Microsoft patch KB982018.

I hope to be clear in my explanation.

Can you help us?

Thanks in advanced for any help.

Kind regards.

Massimo

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P.S. This thread has been moved from Servers>General to  ProLiant Servers - Netservers. -HP Forum Moderator