Handling 'Sequence has no elements' Exception

First() is causing this if your select returns 0 rows. You either have to catch that exception, or use FirstOrDefault() which will return null in case of no elements.


You are using linq's First() method, which as per the documentation throws an InvalidOperationException if you are calling it on an empty collection.

If you expect the result of your query to be empty sometimes, you likely want to use FirstOrDefault(), which will return null if the collection is empty, instead of throwing an exception.


Instead of .First() change it to .FirstOrDefault()


The value is null, you have to check why... (in addition to the implementation of the solutions proposed here)

Check the hardware Connections.


Part of the answer to 'handle' the 'Sequence has no elements' Exception in VB is to test for empty

If Not (myMap Is Nothing) Then
' execute code
End if

Where MyMap is the sequence queried returning empty/null. FYI