IPO 500V2 upgrade from 8.1 to R9

[dowli1]

Hello,

I am new to IP Office and have been requested to upgrade our PBX from version 8.1 to release 9 including Voicemail Pro.

Is there a step-by-step guide available for this? Also, any advice or information (gotchas) regarding the upgrade would be greatly appreciated.

Thanks in advance for your help.
Regards,
Charles.