I though I would give a headsup for a potential problem for some of you using H&R. I encountered a similar problem with both the IRS 2210 (not schedule AI) and the GA 500UET. Even thought I entered, as prompted, the 4 quarterly estimates for both the Fed and GA state, the 2210 section, "Mini worksheet for line 19", the 4th quarterly estimate is zero. The same problem occurs in the GA 500UET in the section "MINI-WORKSHEET for Amounts Paid on Estimate". In both cases, I am forced to override and enter the amount to avoid hefty penalties. In both cases, the 1st 3 quarterly estimates do show-up correctly.