After saving text, doesnt work!

In form 1 there is a Button1
In form 2 there is a textbox1

Button1 is supposed to run the process stated in textbox1
Code:
Process.Start(Form2.Textbox1.text)

This code is run and the appliction has no errors until:

Textbox1.text is saved and when form 2 loads again, the saved text is in textbox1 again
Code:
Textchanged
SaveSetting("Startitup", "Textboxes", "Textbox1.Text", TextBox1.Text)

Form2 Load
TextBox1.Text = GetSetting("Startitup", "Textboxes", "Textbox1.Text", TextBox1.Text)

After i input this save code my button does not run the process in textbox1.

I get this error message:
InvalidOperationException was Unhandled
Cannot start process because a file name has not been provided.

I think the problem is with the saving.
Coz after the saving code the button doesnt run the process
Anybody can help me