Whenever I read your replies I realize how much i have to learn.
Thank you for taking the time. My first problem  was with different
type of variables and how empty was/is handles. Have a lot to learn
there. As for all the Message box calls. You are right, i am using
them to check  results as the function  steps through. Good suggestion
to get to know the debugger. What is the easist way to get started?

One of the main reasons I am using a function is to get it to
automatically update whenever there is a value change to the val
variable. val  will be linked to an RTD cell. i am then going to add
the PrevLowVal value (which will hold the lowest value over some
period of time) to a collection. The function will return the number
of items in the collection. i am looking to determine the lowest
value from a realtime data stream over set  periods of time  and add
thoes values as items to a collection. It all seems to work  except I
was not able to set the first PrevLowVal to a high enough value as a
string. I guess I could use 999999 or convert to a data variable  and
use empty instead of "". Probably convert to data variables and give
that a try.