If the ColdFusion MX server's underlying jrun.xml file is corrupted or truncated due to a manual error when editing and saving the file, the ColdFusion server will not be able to start. When starting CF on the command line you'll see an error and stack trace like the one shown below, and if starting from the Window Services then you'll see a "Service Specific Error 2". To correct this you should restore from a backup jrun.xml file, or copy jrun.xml from another server, or if no other copy exists then install ColdFusion to another server and then take the jrun.xml from it. Be sure to reset any customizations like enabling the built-in JWS or tune the Simultaneous Requests setting.

The top of a stack trace shown when starting ColdFusion on the commandline with a bad jrun.xml file follows:

Starting Macromedia JRun 4 (Build 75991), default server
org.xml.sax.SAXParseException: End of entity while processing comment.
at com.macromedia.crimson.parser.Parser2.fatal(Unknown Source)
at com.macromedia.crimson.parser.Parser2.fatal(Unknown Source)
at com.macromedia.crimson.parser.Parser2.maybeComment(Unknown Source)
at com.macromedia.crimson.parser.Parser2.content(Unknown Source)
at com.macromedia.crimson.parser.Parser2.maybeElement(Unknown Source)
at com.macromedia.crimson.parser.Parser2.parseInternal(Unknown Source)
at com.macromedia.crimson.parser.Parser2.parse(Unknown Source)
at com.macromedia.crimson.parser.XMLReaderImpl.parse(Unknown Source)
at org.xml.sax.helpers.XMLReaderAdapter.parse(XMLReaderAdapter.java:223
at jrunx.kernel.DeploymentService.parseDescriptorURL(DeploymentService.java:70)
at jrunx.kernel.DeploymentService.loadServices(DeploymentService.java:40)