Why do my SMTP/IMAP/POP servers keep going offline in OS X Yosemite Mail app?

I think this for me is related to the whole "wifi issues in Yosemite" problem. I upgraded my MBP 2011 and iMac 2014 to Yosemite immediately. I haven't had a single problem with MBP but iMac has been a fiasco. I associated this to the bluetooth issue whereby I have bluetooth keyboard and trackpad on iMac but not MBP. With iMac until the last patch my wifi would drop out every 15-30 mins and I had to turn wifi off and on to fix it. I tried all the published fixes but none worked. At the same time Mail on my iMac had the dropping out/going offline issue as frequently. Yosemite 10.10.2 mainly fixed the wifi issue but Mail drops out still and the easiest way to fix is literally turn wifi off and on and within 30 secs all mail accounts are online again. Many others by the sounds still have major wifi issues with 10.10.2 I guess we wait for the next version. Frustrating to the extreme to be 100% diplomatic. To watch the Apple keynote the other day going on about "it works" and "beautiful products" knowing that they all know they are literally shipping new product with major wifi deficiencies is galling. All my gear incl router is Mac so no excuses. Anyone else have the same experience?

Pullober -

THANK YOU!!!! I have tried everything else and changing the DNS did the trick immediately.

I had tried everything - still not certain what DNS was - but in mac mail - my gmail - only on my imac - not ipad or iphone - would be grey'd out so that you couldn't access the "get new mail" in the gmail account. The only way to get mail was to shut down the mail program - then re-start. My computer is hard wired into my very fast internet - but I had turned on my wifi for access to something weeks ago. since them I've had the mail issue. I just turned off the wifi and not everything works perfect. I'm going to research this DNS to see if that will allow it to work if the wifi is still on.

I have been using Mac Mail for some years now, really cool to have all my accounts in one place.

A few hiccups along the way, but this present fiasco described by you and mentioned by others has topped them all.

As a result I have removed my accounts from mail- leaving Apple's own mail account which it seems to like and stored the rest in a new folder in Safari.

The mail pages of Yahoo and Google are quite good with other links to avoid boredom.

Even the homepage of my ISP's webmail is presentable.

Drastic, but easy on the coronary arteries.

The move was prompted by a problem with a financial institution for whom my e-mail address was part of their checklist. The SMTP was offline, of course and sending it through another server presented them with an e-mail address other than the one they wanted.

I think Apple are concentrating too much on watches and glasses etc.,and not giving their software the attention it deserves.

The adage about Apple Mac, "It just works!" seems to be getting less than accurate

"If Mail is working elsewhere (i.e. on iPhone or iPad) but not working on laptop, try this. In Mail > Preferences > Accounts, in the 'Advanced' tab, uncheck "Automatically detect and maintain account settings", then check "Allow insecure authentication", then save."

Thanks!!! This worked for me as I had exactly this issue. Funny enough Mail was working and then one day without system updates it decided to deny access on all my OsX computers. iOs kept working, so I new it must be something mit Apple Mail.

Can't access my incoming email since I open multiple account. How can I obtain just one account all inOSX Yoshimites cause I like delete some email account to avoid confusion,thank you.

Like many others, I am also experiencing issues with Yosemite's Mail. Adding my voice here to join the effort to get Apple to do something about this.

It's not my settings, it's not my internet service provider. To get it to work, I have to fiddle around with it—connection doctor, 'send with selected server' button in the dialog box that pops up, and shut down and re-open the program. Sometimes in this order, sometimes repeating these steps.

Eventually after all this bs, the email will send. With the preferences and setting not changed at all.

Please fix Apple, please do fix. We rely on this program to run businesses and to promptly and accurately communicate with others. Please do fix Apple. You can dooo it! Don't be afraid, just give it a shot!

just adding my voice. exactly same issue as described by others here. Mail will periodically and intermittently stop sending, but only on ceratin mail accounts, not all. Like others, I have to tinker with the SMTP servers settings again and again to get it to work. I also make sure that the old keychains are deleted and new ones created.

New, clean install of Yosemite - recently completed to try and address a whole hosts of other niggles. Bad idea, bad idea.... things have actually got worse.

I'm getting tired of this - in the market to replace MBP, but since Apple now insist on supplying everthing with a shiny, glass screen, it won't be a Mac! Decision to also ditch OSX seems more likely, as well, despite many years.

Hopefully theres a fix for this issue soon.

The adage about Apple Mac, "It just works!" seems to be getting less than accurate.

Could not agree more! I like shiny things as much as the next person, but I actually want stuff to work.

I gave up un Mail completely - tried most of the others but have happily ended up with Thunderbird. Don't know why it gets such average press. Working perfectly for me with 4 distinct accounts, got some genuinely useful features, it's free and... it just works!

Hi, appreciate it's going back in time a little. Can you explain changing the DNS settings? Where? Thanks

Since Jun 12th Mail app has been totally unable to connect to any of my SMTP servers to send mail.

I have checked and double checked all the settings, including the SMTP password, but I'm getting no where.

Interestingly FoxMail on the same machine, with the same settings works fine.

I upgraded to Yosemite Mail when it came out and did not have issues till a week ago. At first I thought it was my web host, but they checked and found nothing wrong.

I could access my mail from my iOS devices with not problem, but Mac Mail from both my Air and my iMac stopped working. I tried the different suggestions here, and nothing has given me a stable solution. I tried deleting and reinstalling my IMAP accounts, to no avail. Even my icloud account doesn't work anymore. Accessing my mail from browsers works fine. Apple Mail is the culprit.

Much as I hate doing so, and after 4-5 frustrating days of trying to resolve this issue, this faithful Mac user of 28 years is dropping Apple Mail for now.

Add me to the list of users that's simply transitioning to a different Mail client. I've spent an inordinate amount of time trying to solve this SMTP fiasco - which appears to be tied to the last update of OS X (10.10.4 (14E33b)). Just don't have the time, energy nor inclination to continue with Apple software. I swear, the company has simply lost its way. I've tried each of the fixes suggested in this thread and spent time with support from both of my email providers. Fortunately, both accounts are available by webmail, so that's where I'll go, I guess.

This worked for me:

In the SMTP Server properties I

• un-ticked "Automatically detect and maintain settings"
• Un-ticked "Use SSL"

and fortunately my ISP allows non-ssl connections so it worked for me.

I also downloaded FoxMail from the Mac App Store and it worked without any trouble.