Could you tell us a little more about the settings, not the precise information, but the form of the settings...I have used Orange in France, hope it is the same in the UK. The outgoing mail is of the form for SMTP: outgoing.isp-name.net or com. Is yours of that form or is it different?
The incoming, whether POP or IMAP is usually of the form incoming.isp-name.net or com.
Those are the typical forms, sometimes individual isp's change things a little.
Pop is pop.orangehome.co.uk. Works fine
Smtp is smtp.orangehome.uk. Doesn't work
I have also tried smtp.orange.nett...doesn't work.
I have tried all the ports that orange list and with and without ssl.
I have tried smtp without account details/password and with.
At the moment I have worked around the issue by using the SMTP from my Gmail account.
But that's a fix not the answer.
Since your footer indicates another Mac, have you looked at the mail settings on that machine? Is that one using Orange, also, and do the settings match what Orange has told you to use on the iPad?
Instead of using SMTP as part of the outgoing email server name, try taking tha off, and also try using outgoing instead of SMTP in the server name. The iPad may be adding SMTP by default and you are ending up with SMTP.SMTP. etc.
Start by going into Settings > Mail, Contacts and Calendars > the account with Orange > Delete Account in the red bar at the bottom of the dialog box.
Then you need to have in hand:
Name of the account and the password, incoming host name, SSL yes or no, Authentication if used (usually will be password), Server Port number. Outgoing Mail Server name (usually something like SMTP.ISP.net or com, SSL yes or no, Authentication (usually will be password), Server Port number.
Then go to Settings > Mail, Contacts and Calendars and enter the accont information in the appropriate pages, note you have to go to Advanced to enter the incoming server information details.
This does not take long, but must be done carefully. You may have to try using the account with SSL ON and OFF to see which actually works with your provider.
By the way, you probably would have gotten a faster reply had you started a new post as only those of us who have participated in this thread are notified of a new post. Great that you searched and found this, but a three year old thread doesn't often get seen.