When doing a LON interface to a third party device the Lon Link Manager displays some links with a status of “service type error".
This has been reported specifically with York and Field Server devices but can occur with other manufacturers as well.
G3 (Niagara) ENC, R2 UNC
The default service\link type in R2 and G3 is “standard”, but some third party devices require one of the other types.
Typically the service\link type cannot be changed in the third party device so the default service\link type for the SNVT(s) in question must be changed in the R2 or G3 interface. Reference the R2 LonWorks Integration Guide chapter 8 "Link Manager" or G3 LonWorks Guide chapter 3 "About Lon Link Manager" for details on changing the service\link type.