# Verifying compatibility

Because Natural Access and initialized Natural Access services are dynamically linked, the application needs a way to determine if it is using a compatible library or server. The compatibility level is incremented when any release includes changes that require applications to be recompiled.

To... | Use...
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Check the installed Natural Access core version | ctaGetVersion or ctaGetVersionEx
Check the initialized service version | ctaGetServiceVersion or ctaGetServiceVersionEx

ctaGetVersion, ctaGetVersionEx, ctaGetServiceVersion, and ctaGetServiceVersionEx return the version, the build date, and the compatibility level of Natural Access library, server, or service.

The ctavers utility displays version information about Natural Access services. The version information can be used to report to NMS which revision and build date you are using. Refer to Service version confirmation: ctavers for more information.