Use error handling to debug and manage errors in VIs. The LabVIEW error handler VIs return error codes when an error occurs in a VI. Error codes reveal the specific problem the VI encountered. When you configure an RT target, LabVIEW automatically copies the error code files used by the error handler VIs to the target.

You can use custom error codes with VIs that run on an RT target. Create error files using the Error Code Editor dialog box. Select Tools»Advanced»Edit Error Codes to open the Error Code File Editor dialog box. If you use custom errors on an RT target, you must rename the files to use a *.err extension and then place the error files in the c:\ni-rt\system\user.lib\errors directory or the c:\ni-rt\system\errors directory on the target. (NI Linux Real-Time) Place the error files in the /usr/local/natinst/labview/errors directory.