Why are listed assemblies being excluded

I have a list of assemblies in my NCoverExplorer "Exclusions" report that I did not exclude in any way - either through NCover or NCoverExplorer. The entire modules are being excluded without me explicitly setting up any exclusions anywhere. These "excluded" modules are built in the same .Net solution containing the test DLL's. I have checked that these excluded modules ARE in fact being invoked from one of the tests. My setup is that the nunit tests are being executed and NCover is meant to profile all the assemblies in the working directory i.e. I have not told NCover to exclude anything. However, NCover manages to profile about 70% of the DLLs in the folder, leaving the other 30% unprofiled. I have checked the coverage xml file produced by NCover and noticed that all of the "excluded" modules have no <method> elements within the <module> element in the xml, although these modules contain methods that are in fact being called in the test!!

Also I have verified that the "pdb" files associated with the modules are in the same directory (with the same timestamp) so surely the methods should have been found.

Any ideas what may be causing this, assuming all my configs and commandlines are correct? I have been stuck on this point for 2 days!!

thanks in advance

Ric