How to bypass APM profile if uri is "/rpc/rpcproxy.dll" ?

I "think" your issue might be that you're using eq instead of "starts_with" for the URI in question.

Try setting your second line to the following. I threw in some extra protections in case the client changes case on anything in the URI request:

if { ([string tolower [HTTP::uri]] starts_with "/rpc/rpcproxy.dll") and \
(([HTTP::method] equals "RPC_IN_DATA") or ([HTTP::method] equals "RPC_OUT_DATA"))}{

Hope that helps!! -Cory