I'm reletivly new to Maya and I've been having a problem converting Polygons to Sub-Divs. I downloaded the Cartoon Dog tutorial and followed it as best I could. I had some trouble using booleans: Union so I used the longer method in combining everything. After that I tried to convert the polys into sub-divs then this message appeared in the script editor:
// Error: polyToSubdiv1 (Poly To Subdiv Node): One or more edges is nonmanifold.
// Nonmanifold geometry cannot be converted to a subdivision surface.
// To clean up nonmanifold edges, use Polygons->Cleanup with the nonmanifold option. //
First of all I don't even know what a Nonmanifold is. But I did what it said and I went to Polygons-> Cleanup with the nonmanifold option on. Then after I did that I could change it into Sub-Divs but my model was messed up. Sections where missing and circles were in some sections surrounded by nothing. My model was cut up.