looking for the command to enable email audit on small business server 2011 & exchange 2010?

Take a look at this.

https://technet.microsoft.com/en-us/library/ff459237%28v=exchg.150%29.aspx?f=255&MSPPError=-2147217396

Hi,

You can use the following cmdlet to enable the mailbox audit logging for a mailbox in Exchange 2010 server.

Set-Mailbox -Identity xxx -AuditEnabled $true

For your reference:

Enable or Disable Mailbox Audit Logging for a Mailbox

https://technet.microsoft.com/en-us/library/ff461937(v=exchg.141).aspx

Hope this can be helpful to you.

Best regards,

I find a good PDF in technet gallery that seems to be a good start-up for you. It covers all the required aspects to enable the auditing features in exchange 2010 and track every critical changes into real time : https://gallery.technet.microsoft.com/Enabling-Exchange-2010-368786d3

when i run command i get unknown command or path?

which command are you running?

Set-Mailbox -Identity xxx -AuditEnabled $true

running in powershell is that correct?

Set-Mailbox -Identity xxx -AuditEnabled $true

running in powershell is that correct?

Use EM Shell, not "plain" Powershell..

https://technet.microsoft.com/en-us/library/dd638134(v=exchg.141).aspx

Hi,

The above cmdlet I provided should be run in Exchange Management Shell.

Is there any update with your issue?

Best regards,