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New Member

Attempting to talk to unity over port number 135 ?????

Hello all,

We are trying to tighten up out security around our unity servers.

Ive had been implementing access lists to allow only http (port 80) traffic to pass through the firewall from specific hosts.

The problem we have been having is that my pc (or any other for that matter) tries to contact the unity server while in the middle of browsing it via internet explorer using a port number 135.

I believe this is something called loc-serv but unity (if allowed) doesn’t respond to them. This causes a delay of approx 10 sec while it retries and eventually times out and is seen by the users as ‘unity running slow’.

Does anyone know what this is and why its happening ???.



New Member

Re: Attempting to talk to unity over port number 135 ?????

It sounds like your trying to run Active Assistant/CPCA through your firewall. What you're likely seeing is a delay as the client machines try and then fail to load the Media Master plug-in (which relies on DCOM).

Unfortunately, DCOM uses a dynamic port range somewhere between 1025 - 65535, which makes it almost impossible to run through a firewall. Microsoft has published some tech notes on how to limit DCOM to a specific port range, but that has not been fully tested with Unity yet.

I hope that helps,


New Member

Re: Attempting to talk to unity over port number 135 ?????

FYI, Microsoft's tech note on limiting dynamic port ranges can be found here:;en-us;154596