Exchange 2010 SP3 bulk email delete

I have an administrator mailbox on my Exchange server where spam goes, so it's loaded with mail and I want to bulk delete alot of it. I had the powershell command once and it worked but I lost it.

I tried this
search-mailbox -Identity administrator -SearchQuery "Received:> $('1/01/2012') and Received:< $('1/31/2012')" -DeleteContent

and it seems like it worked, I got a ResultItemsCount : 2448 ResultItemsSize  : 111.4 MB (116,811,965 bytes)

Yet email from January 2012 is still in the inbox.

I also tried replacing search-mailbox with get-mailbox
get-mailbox -Identity administrator -SearchQuery "Received:> $('1/01/2012') and Received:< $('1/31/2012')" -DeleteContent

This caused an error - A positional parameter cannot be found that accepts argument '-SearchQuery'. blah blah blah

Any ideas? Thanks a lot.
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SearchQuery  is not a parameter to Get-Mailbox and because of this would not work
Taka e alook at this post from Technet Forums maybe it will help you more. Check also on the left side of the page section "Top related threads"

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