compiler is complaining about the s.Split(delim) statement below

See more:

C#3.0

C#

I have a text file where items on each line are delimited by "|".
I'm reading each line into a List of strings. Then processing each line.
As you can see this is pretty straight forward.
when the compiler see s.Split(delim); it says:
"The best overloaded method match for 'string.Split(parms char[])' has some invalid arguments"
I do not understand why the error exists or how to fix it.
Please assist with a correction of the code below.
Thanks

List<string> TempList = new List<string>();

using (StreamReader r = new StreamReader(Filename))
{
    string line;
    while ((line = r.ReadLine()) != null)
    {
        TempList.Add(line);
    }
}

string delim = "|"
string[] ControlParts;
foreach ( string s in TempList) {
    ControlParts = s.Split(delim);
    _MeditechConnections.Add(ControlParts[0]);
}