Out of the blue Rhino Script error message

Hi, I have been using some rhino script for a long time with no problem all of a sudden I get this message, can some one suggest why this is happening, Thanks

Can you try it on another rhino file? is the error exclusive to this file?

Did you write the script? You usually get an error like that where some function had an error and returned Null and that wasn’t accounted for.

Thanks for the replys, yes I closed and reopened rhino with another file, same problem. No I did not write the script Pascal did for me years ago, so was always working fine.

Hello - that error message is generally from a script designed to load at startup - mine are usually that way - so to sort it out, drag and drop the rvb file onto Rhino to reset that load at startup part.