Migrate to 2.3 causes bad crashes

[Ian Vink]

I moved to Lucene.net 2.3 from 2.0.0
I am getting a cryptic, "Could not find file
'd:\interfaith\INDEX\English\segments.gen' " message after I call this:

IndexWriter writer = new IndexWriter(languageINDEX, analyzer, true);

Where languageINDEX is a string "c:\Index\English" folder.

There is no segments.gen in 2.0.0, but should moving to a new index cause
that error?

I tried deleting the index and letting 2.3 remake it, but to no avail.
It always wants segments.gen

Any ideas?