In case anyone can get anything useful, I have an ear file that works well and very reliably (over 6 months) on my Linux server running JB 4.2.1. This ear uses MS sql drivers and connects to MS SQL on mt 2003 SBS server. When I move THE SAME distros of Java, JBoss, MS SQL drivers ear etc to the 2003 server running as localhost ... or to a DNS name or IP number on the WIn server , I get this message. Theenvironments couldnt be more similar other than the one is Unix, the other WIn2003. I'm about to check for copies of the drivers in the ear - they will, of course, be from the SAME DOWNLOAD from MS. Chris View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4133006#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...