Created attachment 23059 [details] source and excel to re-produce the bug Cloning "once" a sheet with autofilters is OK. Cloning a cloned sheet without autofilters is OK. But cloning a cloned sheet having autofilters causes workbook to corrupt. Tested with latest r729456. Source and examples attached. Got some old POI versions archived, and with r693203 my test case ended up in null pointer exception, but since r693221 results current behaviour.
This problem should be fixed in trunk. Please try with a nightly build - see download links on http://poi.apache.org/ or build yourself from SVN trunk, see http://poi.apache.org/subversion.html
(In reply to comment #1) > This problem should be fixed in trunk. Verified this, thanks. Good to see the older bugs getting bashed too!