System.argument exception illegal characters in path

Question

im using microsoft visual c# express and its database.
 
through my c# program i wanted to retrieve a folder path from the database to select files.but im getting this error.please help.
i have created a column 'folder_path nvarchar(50)'
my folder path is : @"f:/pick_up"
 
if i put folder path as 'comp' it reads.i guess the error has something to do with special characters @,/ and ".
reply asap.thank you.