Hi, I stumbled upon this on accident, and I wanted to share my experience. I have not had any issues at all upgrading from 4.7.4 to 5.2.2. I have done this particular jump several times, and the only thing you have to watch (outside of the changes in the windows TA) is that the upgrade instructions are followed in their entirety. These are older Splunk machines as well, so it is usually a Splunk upgrade and then ES which updates the TA after. After the upgrade is completed, I run a searches to verify no old settings conflict with the new settings. In summary, there are a lot of changes that happen, but the ES installer takes care of most of them. ES 5.2.2 has never failed on an install for me, and I have done this particular upgrade several times. Be sure to modify searches to reflect the new changes in the Windows TA after it is installed. Also do not skip ANY steps. I did this, and I have not failed yet. ... View more