SSIS deployment failed - working with files

I've developed a simple SSIS package that will open a csv file, select a number of column, add two derived columns and then copy the results to a file. This works within visual studio (even if it takes ages) where I constructed it. The problem is when I attempt to deploy it to our sql server it fails. It keeps say that: "The specified parameter value string is too long. The string must be no more than 8000 characters." But I have no idea what it is talking about as none of my columns is over 1000 characters. There isn't much info on this error but is it possible that the number of rows (400,000+) is the source of the problem?