Script Component in loop tries to evaluate connection

I have a script component which loads a file which is in a custom format. The script component is inside a For Each Loop Container and it uses a flat file connection manager. The loop sets the connection string for the connection manager.

The problem I'm having is that the connection string needs to be set to something every time that I start the package but I don't know ahead of time what file there will be, so I get a System.IO.FileNotFoundException error on the script component. If I manually set the variable for the connection string and point it to a file that exists, then the package runs fine but at the end of the package the connection string is set to the last file loaded and this file will no longer exist the next time the package runs.

I hope this makes sense...

Set the DelayValidation property to True for the connection (and data flow task if required).