Is exchange 2007 classed as a cluster? OS is W2K3 Ent R2 SP2 x64 on all 3 servers I am trying to add a LUN that is 3.2 TB and convert it to GPT to get full use, however it fails, MS articles point to http://support.microsoft.com/kb/919117/en-us - A hotfix is available that adds support for GUID partition table (GPT) volumes that are larger than 2 terabytes on a Windows Server 2003-based server cluster This hotfix is aimed at 32 Bit, so reluctant to apply this hotfix. Appreciate if anyone came across this

Hi Well, Exchange 2007 uses Failover Clustering in Windows Can you use diskpart instead of the GUI?Jonas Andersson MCTS: Microsoft Exchange Server 2007/2010 | MCITP: EMA 2007/2010 | MCSE/MCSA Blog: http://www.testlabs.se/blog

That's a very large LUN to add to Exchange as a single unit. Have you calculated the IOPS for the number of mailboxes etc. that you are going to be putting onto it? Neill

Thanks both for your comments. No can't use either the GUI or diskpart DISKPART> convert gpt The disk you specified cannot be converted to GPT. Please select an empty basic MBR disk to convert. This extension is just buying us some time until the powers that be set up some form of regulating the size of mailboxes and then hopefully looking to move to Ex 2010. With our Ex guru, looking at rather than extending is splitting the mailboxes onto two volumes instaed of one If still needs must then will have to find a test cluster and run the hotfix on that Thanks again