All of the LNC functions return an error code; zero means no error. These are the error code values which may be returned:
| Value and Macro | Reason | 
|---|---|
| 1 = LNCE_NODE_NFND | node not found | 
| 2 = LNCE_SECTION_NFND | section not found | 
| 3 = LNCE_PAR_NFND | parameter not found | 
| 4 = LNCE_PARSIZE | the size of the output buffer is not big enough. The size is set to the required value. | 
| 5 = LNCE_PARTYPE | the parameter cannot be set to this type | 
| 6 = LNCE_BADVAL | the value to be set for the parameter is invalid | 
| 7 = LNCE_EXIST | the element already exists | 
| 8 = LNCE_RESTARTNOT | on calling DoRestart, the user selected No on the restart Windows dialog | 
| 9 = LNCE_NOACCESS | the client does not have administrator rights | 
| 10 = LNCE_READERR | reading a value failed | 
| 11 = LCNE_WRITEERR | writing a value failed | 
| 12 = LCNE_NOMORE | an enumeration function has reached the end | 
| 13 = LNCE_NOSET | the parameter cannot be set | 
| 14 = LNCE_DEDIZERO | there are no nodes in dedicated mode | 
| 15 = LNCE_DEDITOOMANY | there are too many nodes in dedicated mode | 
| 16 = LNCE_SHAREDZERO | there is no node in shared mode | 
| 17 = LNCE_SHAREDTOOMANY | there are too many nodes in shared mode | 
| 18 = LNCE_DEDIHOLE | there is a hole in the core use in dedicated mode | 
| 19 = LNCE_PROP_NFND | property number is invalid | 
| 20 = LNCE_NODEDEVS | node cannot be deleted as it owns devices | 
| 21 = LNCE_MEMTOOMUCH | total memory too much | 
| 22 = LNCE_NODEL | the parameter or property cannot be deleted | 
| 23 = LNCE_NUMPROC | the bootparameter NUMPROC is greater than or equal to the number of available cores | 
| 24 = LNCE_VPORTTOOMANY | there are more than 4 virtual serial ports | 
| 25 = LNCE_VPORTINUSE | the virtual serial port is already in use | 
| 26 = LNCE_NODERUNNING | the requested change cannot be made while the node is running |