Problem creating RAMDirectory - The given path's format is not supported.

[Michael Barbarelli]

I'm at my wits end with the following.  Has anyone encountered this
before?  Thank you very much in advance.


The given path's format is not supported.
Description: An unhandled exception occurred during the execution of
the current web request. Please review the stack trace for more
information about the error and where it originated in the code.

Exception Details: System.NotSupportedException: The given path's
format is not supported.

Source Error:

Line 342:            this.indexDirectory = @"C:\obi_index_backup";
Line 343:
Line 344:            Lucene.Net.Store.Directory ramDir = new
RAMDirectory(this.indexDirectory);
Line 345:
Line 346:            this.searcher = new IndexSearcher(ramDir);