What's the extension for Interpolation files?

When you go to write the file there is no extension by default (I don't know why Fluent did this, but they did). However when you go to read the file, by default it's looking for a *.ip file. So, when you go to write the file, if you don't include the .ip on the end, then it will have no extension. You can still read the file, it just doesn't show up by default because of the file list filter. Just turn off the filter (In UNIX delete the *.ip in the address bar, in Windows, select "show all files").

Hope this helps, and good luck, Jason