Sorry, posted the wrong traceback in the previous post - the traceback happens after the buffer space errors (which are the first ones to appear). Also, once this happens, all "connection related" things starts giving problems (download managers, mail clients, etc.). From there on it seems everything that needs to connect to something remote cannot do it. Here is the correct traceback: Traceback (most recent call last): File "V:\ZopeInstanceHome27\Products\ZIMSViewerPlugins\PyIMSConnector\TestMap.py", line 26, i n setUp self.server = TestServer.getServer() File "V:\ZopeInstanceHome27\Products\ZIMSViewerPlugins\PyIMSConnector\TestServer.py", line 29 , in getServer TestServer.environment['ArcIMSProxyPassword']) File "V:\ZopeInstanceHome27\Products\ZIMSViewerPlugins\PyIMSConnector\Server.py", line 37, in __init__ self.reload() File "V:\ZopeInstanceHome27\Products\ZIMSViewerPlugins\PyIMSConnector\Server.py", line 45, in reload responseString = self.connector.sendRequest(requestString) File "c:\!projects\python\PyIMSConnector\ConnectorBase.py", line 45, in sendRequest raise error error: (10055, 'No buffer space available')