Final answer:
The error in ordering a new test in the LIS is likely due to a configuration issue within the system, user permissions, or a communication problem between the LIS and the analyzer.
Step-by-step explanation:
The most likely cause of the error when an accessioning department receives a request for a new test but an error is displayed is a configuration issue within the Laboratory Information System (LIS). When a new test is added to an LIS, it requires meticulous setup involving test codes, order entry protocols, and result interfacing. If the new test cannot be ordered despite other tests functioning correctly, it could imply that there is an issue with how the test was configured in the system, such as incorrect or incomplete mapping to order entry procedures or missing linkage to the analyzer's test repertoire.
Another possibility could be user permissions; the staff attempting to order the test might not have the appropriate permissions to access the new test. Additionally, potential problems with communication between the LIS and the analyzer for the specific new test setup should also be considered.