I received an error message solving an unsteady flow problem with VOF: Error: GENERAL-CAR-CDR: invalid argument [1]: improper list Do any one know what it is and how I can fix it? Thanks a lot!!!

Sean

And it says "Error Object: #f".

Sometimes I'll see error messages like that if I try to monitor the values at a surface, but the requested action doesn't make sense (like if it is carried over from a previous case). Are you trying to write values to a file?