Cannot Send Mail Sender Address Invalid

aahmie's solution was the only one that worked for me -- resetting the iPad by holding the power key and home key down until reset.

SSL turned on and off, authentication left blank then filled in, deleting and reentering account, syncing via computer for settings then deleting and reentering manually -- NOTHING has worked for 3 months until the resetting of the iPad.

Good luck. This needs to be prominently displayed on Apple's support site. (Ironically, one of their suggestions is, if all else fails, to get a gmail account and route all your mail through it. Wow. That's pretty cheesy...)

I have had the same problem since I have had my iPad. I have tried everything short of resetting everything. Today, out of frustration, I called Apple. The nice tech gal asked me to send an email to myself at the email address I was using on my iPad. I did and it went through with the other 10 emails I had in my out box.

The only thing we could figure is that by sending an email to myself, the system (or ISP) got that it is a valid account and therefore will now send emails.

I have had this same problem with my iPod Touch but this same thing DID NOT fix my Touch.

Another thing you may want to look at is turning off the SSL for the Outgoing SMTP server.

Cheers!

I mentioned that I had the same problem with my iTouch. Found the solution and this may be of assistance with the iPad also for those that are having problems.

Solution discovered.
On the Mac the ports used for the SMTP server are set to the Default (25, 465, 587) however the default on the IPod Touch is port 587.
Cox apparently uses port 25 on it's SMTP server.
Made that change on the IPod Touch and all is fine.

I made the same change on my iPad and now all is well.

If this is true for Cox people, others should look at this with their ISPs.

Cheers!

I tried aahmie's suggestion and most of the other suggestions posted and I still get the message"The sender address was invalid". Any further suggestions? I receive mail. I have configured the iPad in the same way as my iPhone, from which I can send and receive messages so I don't know what the problem is.

Guys
I just got an iPad and configured my POP email. I was able to receive and send emails for some time... but not long: after a couple of days , I could receive but not send emails. "Sender's address invalid" error 😟

All the fixes on this post make me think ... The fixes are so different: sometimes it is just an ISP setting. OK, so that's all right. But when the ISP settings are OK... And in my case: it worked ! But for some reason it is now broken.

Maybe there is a bug in the email account settings part of the iPad!
Only Apple can help ...

By the way: the only way I found to fix this is:

Delete the POP account
Re-create it (with the same settings)
And re-set the iPad (it would not work without resetting)

Obviously, this is not what I want to do every other day 😟

I am having very similar issues. I have been sending and receiving email with no problem for a couple of weeks. I am now traveling, and using the hotel and airport public wifi and suddenly I'm able to receive email but not receive it. I am using a Roadrunner (Time Warner) server. I did nothing to change my email settings, but now every time I attempt to send I get the Mail Sender Address Invalid message. What gives? It doesn't seem like anything should have changed.

I am having very similar issues. I have been sending and receiving email with no problem for a couple of weeks. I am now traveling, and using the hotel and airport public wifi and suddenly I'm able to receive email but not receive it. I am using a Roadrunner (Time Warner) server. I did nothing to change my email settings, but now every time I attempt to send I get the Mail Sender Address Invalid message. What gives? It doesn't seem like anything should have changed.

Steve
Although, very frustrating, your issue has probably another cause. You see, most ISPs around the world do not allow to send emails when not connected to their network (e.g. When your travelling and use an airport or hotel hotspot).
The way I solved it : I setup a free gmail account and use the smpt.gmail.com outgoing sever when roaming.
That is not solving my (and many others) problem, as I have it when I'm at home...
I figured out that I start getting the problem after a synch with iTunes... It is definitely a bug.
I hope this helps
Pascal

Pascal--thank you for the reply.

After I sent the post yesterday I realized that I had synched with iTunes before leaving on my trip, which I realize now is a big mistake. I am beginning to think that the only recourse that I am going to have is to delete the current email account and re-create it. I hope that Apple is aware of this bug as this seems to be a perennial and very annoying problem for a lot of people. It seems that when using one of the pre-approved email accounts (such as gmail) there is no problem, but for anyone using a different ISP they are lost in the wilderness. Even creating the account was an ordeal that I finally solved by viewing several iPad blogs.

Yes, I could route through gmail, but that seems to be a very inelegant solution for a company that prides itself on the elegance of it's software and design.

I have to say that again you are right. When I returned home tonight and was back on my personal wifi everything was back to normal the emails that sat in the outbox for three days sent like a charm. I guess when I travel I should route my roadrunner email to my gmail account.

Thank you for the reply!

I bought the 64GB 3G iPad on the day it was launched in Australia for business use.

In my home-office, I use the domestic WiFi plan which is considerably cheaper than the mobile 3G plan I bought for use on business trips.

The plans are from two different providers which means that outgoing emails have to be routed through two different SMTP servers depending on whether I am using WiFi or 3G.

And therein lies the problem. While on a business trip, I found that I could not send any emails over 3G with an error message to the effect ‘Invalid Sender Address’. The emails were just stored in an ‘outbox’ which only appears when there is a problem. Yet these emails fired off when I got home and had switched off 3G and turned on WiFi.

NOTE: the error message is *badly worded* as there is no problem with the sender address... read on for the *real issue...*

Playing around with the email account settings, I have found that the iPad *gives up* on sending emails after failing to send though the ‘Primary SMTP server’. Contrary to the text at the foot of the server settings page, *it does not even attempt to try* the ‘Other SMTP servers’ listed that, in my case, have always been turned ‘on’.

THE FIX: Permanently turn ‘off’ the primary SMTP server and ensure servers for *all active carriers* are listed and turned ‘on’ in the ‘Other SMTP server’ list.

This forces the iPad to try the servers listed in the ‘Other SMTP server’ list till the right one for the active communications channel (3G or WiFi) works and fires off the email.

This checking takes a little longer but ultimately, it works.

This has been logged with Apple and has been acknowledged as a 'problem to be resolved'.

Hi guys,

For all of you who seem to have tried "everything" such as resetting, deleting your email, rechecking your smtp etc. and its still not working, I may have the answer for you.

Unlike other iPad users who have been fortunate enough to just enter their username and password or turn SSL on/off...you guys are lucky. I tried this and other methods and was unfortunate every time to the point where in one blog I read that the only solution if all else fails is to redirect your mail through gmail. This was unacceptable for me.

After a combination of tweaks, this is what worked for me. If you're a user that has tried everything else and it still ain't working, then hopefully this will.

Step 1:
Go to your smtp mail settings
You will see your primary mail server and may also see a list of other mail servers with an "on/off" switch beside them. Turn these all to "on".

Step 2:
Now go to your primary smtp server details
Enter your username and password
Select SSL on
Authentication: Password
Port: 573 --> VERY IMPORTANT

Step 3:
Save and exit

You do not need to restart, try sending email from the account you just changed. If it works repeat the above process for your other accounts.

Message was edited by: Artha666

I have developed this same problem in recent days. None of these fixes have worked for me. I found that if I turned off wifi my 3G kicks in and sends them. Irritating. The iPad has been my first experience with Apple. I have other problems. Let's just say I ain't buying stock.....

Got my ipad today and was having the same problem sending email through my Cox account, always getting the sender address invlaid error message. In settings under Outgoing I changed the port to "25" and now it sends and receives fine.

Bill