I took at look at this and my guess is that the red line is throwing an error, but the catch statement just absorbs the error so you don't see it. I would add a breakpoint inside the catch and then step through the code to see what error you're getting.
Maybe sTraceFileName isn't pointing to a valid trace file or something? Or maybe that trace file is still being written to? My guess is that the exception you're seeing from your post above is from the line I highlighted in blue... so maybe the code above
it didn't work as expected.
Dim issuccess As Boolean = True
' Open the trace file as a reader
Catch goof As Exception
issuccess = False
Dim numfields As Integer = 0
>= 1 Then
numfields = myTraceFile.FieldCount
numfields = 17