Import Files Do Not Exist

I have a job that calls about 5 DTS's. Each DTS imports a text file. The problem is that some of the files may not be there every day. How do I exit the DTS without an error if the file does not exist, but I want my job to keep running...how about using an activex task to check for file and if file not found then Main = DTSTaskExecResult_Success, each of this task will then trigger the respective DTS package.