PE 610 server losing connection to LUNs on MD3200i

We have a Dell PE610 W2K8R2 as a host connected to 2 Dell 6224 switches and an MD3200i Storage device.

I keep losing my connections this week to the LUNs, when they do appear in Disk Management I am unable to initialize the disks.

2 disks are pass through and 2 disks have fixed vhd. I get an Incorrect Function when I try to initialize then it hangs and I reboot and the LUNs are gone.

I have edited the registry key to increase the timeout as suggested but no luck. Anyone seen this error and know of a fix??

thanks

Marc error below

Log Name:      System
Source:        iScsiPrt
Date:          6/5/2013 11:43:04 AM
Event ID:      20
Task Category: None
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      C27NSDSAPRTHPS1
Description:
Connection to the target was lost. The initiator will attempt to retry the connection.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="iScsiPrt" />
    <EventID Qualifiers="49152">20</EventID>
    <Level>2</Level>
    <Task>0</Task>
    <Keywords>0x80000000000000</Keywords>
    <TimeCreated SystemTime="2013-06-05T16:43:04.926683300Z" />
    <EventRecordID>129485</EventRecordID>
    <Channel>System</Channel>
    <Computer>C27NSDSAPRTHPS1</Computer>
    <Security />
  </System>
  <EventData>
    <Data>\Device\RaidPort4</Data>
    <Binary>000090000100000000000000140000C00000000000000000000000000000000000000000000000006900

71006E002E0031003900380034002D00300035002E0063006F006D002E00640065006C006C003A0070006F00770

0650072007600610075006C0074002E006D006400330032003000300069002E003600370038003200620063006200

3000300030003500380062003700630034003000300030003000300030003000300034006500380033006100620034

003300</Binary>
  </EventData>
</Event>