problem with saving data

We are having a problem with our medialab 2008 script, in that it seems to unreliably save data. We're not really sure what's going on-- sometimes it saves the data, sometimes it doesn't (even with the same subject number). There are no error messages. What's especially puzzling is it seems to happen to anyone doing the experiment at the same time-- so, 4 or 5 subjects on different computers would not have their data recorded, but then subjects running the same script on the same computers an hour later would be fine.

Is there anything you know of that might be causing this? Perhaps some keystroke at the end subjects might be pushing? Would a fleeting network disconnection cause it?

If you are running multiple subjects simultaneously and having the data written to a central location (instead of locally, e.g., on a server folder), you can get data collisions if you don't use "unique machine codes" that are appended to the individual data files to ensure that no two files with the same name are opened or written to at the same time. Given your mention that it is more likely to happen with multiple sessions running than with one session, that would be my best guess.

For more detail, see Using Alternate Data File and Unique Machine Code here:
[URL]http://www.empirisoft.com/medialab/help/preferences.htm[/URL]