I am trying to do high speed data acquisition, and save data to file. I will acquire a large number of data, so saving to just one file would result in my file blowing up in size. Hence I would like to save my data to mulitple files. I am trying to figure out how to open multiple files, then chose which file to write to. My approach is to open/create multiple files and save their refnum in an array. Then i would like to pick which file to write from this array. I have attached my VI, whatever I have so far. I seem to get errors like, "Duplicate path" or " An input parameter is invalid. For example if the input is a path, the path might contain a character not allowed by the OS such as ? or @." How would I get started with this problem?