Strange error: Exception has been thrown by the target of an invocation

Question

I used open source program in part of my project, implant code in my project well and it worked good. but i'm new in programming and sorry to say this: i did not remember what did i do to this project.i tried to configure project, and change platform to x86 and x64 and AnyCPU then i build my solution and have some error about target CPU, so i change every thing(im not sure!) to default. Then i build solution and get this error when i wanted to execute open-source section of my program :

Exception has been thrown by the target of an invocation. An unhandled exception of type 'System.Reflection.TargetInvocationException' occurred in mscorlib.dll

I test this part of my project in open-source project. but there was not no error. every thing are same but my project thrown an error.

if this help to help me: It is part of my program that thrown error and open-source program without no problem!

ArrayList pluginsKeeper = new ArrayList();
StreamReader pluginReader = new StreamReader("Agent.dm");
string line;
char[] separator = { ' ', '\t', '\n' };
string[] tokens;

while ((line = pluginReader.ReadLine()) != null)
{
    line = line.Trim();
    if (line.Length > 0 && line[0] != ';')
    {
        tokens = line.Split(separator);
        if (tokens[0].Equals("Agent1Default"))
        {
            defaultChecked = int.Parse(tokens[1]);
        }
        else
        {
            System.Runtime.Remoting.ObjectHandle oh = Activator.CreateInstanceFrom(tokens[0], tokens[1]);
            pluginsKeeper.Add(oh.Unwrap());
        }
    }
}
pluginReader.Close();

its thrown error here: System.Runtime.Remoting.ObjectHandle oh = Activator.CreateInstanceFrom(tokens[0], tokens[1]); .

Answer 1

this problem has strange answer! When windows wants to save file in windows for later you, it used '/' instead of '.'. So my program couldn't read the file!

I hope this help someone.