Loading config file does not remove prior configuration?

[shadowplay101]

After factory defaulting the Cisco 2504 WLC, I go to through the wizard for initial config then log into the web interface and download my 'full' config file to the controller. After the reboot I upload the config file to my PC and compare it to the original file, but it does not  match.

Any ideas what could be causing this?

[Saurav Lodh]

Follow these guidelines when working with configuration files:

•  Any CLI with an invalid value is filtered out and set to default by the XML validation engine. Validation occurs during bootup. A configuration may be rejected if the validation fails. A configuration may fail if you have an invalid CLI. For example, if you have a CLI where you try to configure a WLAN without adding appropriate commands to add the WLAN.
•  A configuration may be rejected if the dependencies are not addressed. For example, if you try to configure dependent parameters without using the add command. The XML validation may succeed but the configuration download infrastructure will immediately reject the configuration with no validation errors.
•  An invalid configuration can be verified by using the show invalid-config command. The show invalid-config command reports the configuration that is rejected by the controller either as part of download process or by XML validation infrastructure.