I use Zimbra for my 4 yahoo, 1 hotmail and 1 gmail account. I use the version 7.2.5.
About a month back, I started getting delivery failure errors from one yahoo account. it said, Human verification required.
Based on the information available on the net, I did the following:
1. I removed and re-added the yahoo account to Zimbra. Problem persisted.
2. I logged in from web client, and entered the Captcha code a few times and then when it stopped asking me for it, I tried to access again from Zimbra, but still the same error
3. Contacted yahoo, but they pointed me to Zimbra. I did not believe them.
3. To isolate the issue, I installed various other desktop mail clients, eM, Windows Mail, Thunderbird. I did not get the same error from them. So it seems yahoo support was correct. The problem is unique to Zimbra and this specific email account.
With the above background, I would like to know if anyone can help solve the problem. I would hate to move to another desktop client. been using Zimbra for a long time. It also works well with my other yahoo accounts, but just fails for this specific account.