We have 4 projects where we are using Ignition. At one site, we used 64bit versions of java/ignition and it worked fine. At the second site, we used 64bit versions of both application and it did not work. The project has around 8000 tags and i did not have time to change the path for all the sql tags and hence stayed with OPCDA. At the second site, I am using 32 bit version of both application and it is working now. I am not sure why the 64 bit combination worked at one site and not in the other site.