Yahoo server unavailable. I am not able to get into yahoo account. iPhone 4S

I have iphone 4 and get error msg as above and have followed the steps given. Do I use the same username as the email address if that is the same?

I had ipad 2 with yahoo working fine. Yesterday I got iphone 4s with ios 5.1.1 and would not work. I got the 'server unavailable' error. Then after syncing my ipad with itunes on my laptop and doing an upgrade to ios 5.1.1 now yahoo no longer works there either.

I followed the instructions about adding 'other' email and setting up witht the imap settings and it worked for me on both devices, however it only syncs email and notes. Contacts and calendar do not sync. I was up very late and still no solution. Seems like there are many threads on various forums about the yahoo problem syncing with 5.1.1 ios, specifically contacts or calendar.

Any new insights on solutions would be appreciated.

I just got the iphone 5 and i have 2 yahoo email addy. I was able to register one of my account using the yahoo.com server... I tried imap.mail.yahoo.com for my "other" yahoo email but to no avail.. followed the outgoing and the incoming server, tried to delete the other acoount so I could register this account. I even changed my password... Still, I could not register it... This is driving me crazy!! heellp pleaseeee...

I just had this problem and this was fix in 2 minutes!! I called Apple Support and they want $70 to fix it, go figure$$$$$$ Tks Guys

But does this fix also sych Contacts?

If no, is there a fix for both Yashoo Mail and Yahoo Contacts?

Thank you

While the solution of using "Other" and entering all the server information manually worked for me, it would not allow me to sync anything by my mail and my notes with Yahoo! That is, I could not sync contacts (calendars, nor reminders)

I wrote to Yahoo! asking for help, and they sent me to a typical troubleshooting page with a bunch of, "have you tried turning it off and on again?" steps, but on that page it said:

if the steps on the help page did not fully resolve your issue, I'd suggest following these additional steps to continue troubleshooting:

• Set up your Yahoo! Account on your iPhone using the Yahoo! option. Please make sure that you enter your new password when setting up the account.
• Make sure that your iPhone is not set to Fetch new mail manually. To verify this, please take the following steps:

1. Open Settings.
2. Select Mail, Contacts, Calendars.
3. Select Fetch New Data.
4. Ensure that Push is ON.

I had "Push" turned on, but I had "Fetch" set to "Manually."

When I changed it to something like "Every 15 Minutes," it started working perfectly, and it allowed syncing of all the Yahoo! features (including my contacts).