Updates over proxy dont work

Hi all,
we just test esm and the client update over the esm proxy dont work. The cache folder is empty an the client give a “timeout-error”.

Our LAN reach the internet by proxy, ist it possible that the esm proxy dont work behind a proxy.

What ist the best practice to update the clients?
We have tested COU, it work for signatures but product update end with file not found, also we want to use the esm to update the clients.

Any hints?
ESM is on Win7 Pro / Clients Win7Pro too


Hello Gerd,

Please make sure you add your proxy settings in the CESM Configuration Tool, under the Internet&Email Setting tab.
Also, please make sure the ESM Proxy Cache cache port is opened for inbound connection on your Server. By default the ESM Proxy Cache port is 8080, but can be changed in the CESM Configuration tool.

The policy that you apply on your endpoints needs to be configured with your ESM Proxy Cache settings accordingly: Comodo Help

Hallo Radu,
thanks for your reply.
On the Server (esm) is no active firewall and the settings for proxy and clients are right.
Do you know how the proxy work, is he download the updates by it self or must i copy any files to the cache-folder.
Are there any special port to be open on the firewall to the internet?


Hello Gerd,

Whenever an endpoint needs to update (CES updates itself each hour by default - but it can be changed), it will try to pull the updates from the ESM Server. The ESM Server will check if it has the latest Virus Definitions. If it doesn’t, it will pull it from the Internet (download.comodo.com). If it does the update process for the endpoint will begin. If the ESM Server is offline, the endpoint will update from the Internet.
Select the check box ‘Provide cached content if content source is not available’, in the CESM Configuration Tool, for the endpoints to update from the proxy server if the content source is not available via Internet.

ESM communicates with download.comodo.com on port 80 (for virus definitions updates), with downloads.comodo.com on ports 80 and 443 (for product updates) and with accounts.comodo.com on port 80 and 443 (for licensing purpose).