unknown sender error from relay.force9.net - possible solution to do with force9 vs. f9 address?

[#1]

I am hoping that a superuser or moderator may be able to put this information in the right place or bring it to the attention of the right people. 

I have been struggling for the last 2 days with not being able to send emails from my force9 account, getting an 5.7.1 unknown sender error where it worked fine before. 

After speaking to plus net, they told me my account had been migrated  (I had not yet had the migration email) .It looks like the migration date is when the problems started. 

I was given some very strange advice re ports etc. from Greenby's AI and was kept waiting unsuccessfully for a human agent when I queried it.

However, it seems (unless this is a big coincidence) that I have found a solution - my account settings in Mail on Mac had the email address I was sending from as xx@xx.force9.co.uk,  whereas I noticed that the Greenby dashboard showed it as xx@xx.f9.co.uk.

I decided to add the f9 version as one of the emails to the account and hey presto, when I choose this as the address to be sending from, it works!

I double-checked, and it still does not work with the force9 version of the email address.

Curiously I did originally get two identical emails from Plus Net advising of  the coming migration, one to the  f9 and one to the force9 version of my address. I was told by the Plus Net Agent today that these are basically the same, but I am now wondering whether these are somehow treated as different accounts in the migration and Greenby have migrated  the f9 one, but not the force9 one?

Apologies if this is not useful, but if it is, maybe someone could put it in the right topic so it spares someone else 2 days of hairpulling. 

[#2]

Is the sending address a real mailbox or is it an alias?

@plusnettony  / @dave  - this seems to echo my test reposts made elsewhere related to aliases.

What is the correct domain for these accounts?

• account.force9.co.uk
• account.f9.co.uk

Previously they were synonymous.  Are users expected to change to the short hand version?  What does that mean to the outside world for mail addressed to account.force9.co.uk - will it be received correctly?

Replying is likely to be problematic as the client is likely to adopt from as account.force9.co.uk.

[#3]

I'm not aware of anything but I'll do some digging and keep my eye our for similar issues. 

[#4]

Thanks for taking this up!

[#5]

I'm also experiencing the "unknown sender" error. Currently unable to send any emails. I've received my migration email but Greenby seem to have missed something somewhere along the way.

[#6]

Hi Walkham,

What worked for me was changing the email address  (not the account name, that is still force9) associated with my account in the email client settings to the f9 rather than the force9 version. Maybe you could check on the Greenby dashboard what email address they have for you, and whether it is f9 or force9, and then check whether this is the same as the email address you are using to send from.

This got rid of the unknown sender error for me. 

Simply put, it looks like I can still receive emails either to the force9 or the f9 version of my address, but I can only send from the f9 version. 

I am hoping that I am not storing up problems for the future doing this.

But for now it seems better than trying the weird unencrypted non-SSL settings advised by Greenby chatbots.

[#7]

I have raised this btw, but I welcome further examples. 

[#8]

@walkham 

A warm welcome to the forum.

Are you Force9 / F9?  There are various scenarios for the "sender unknown" error event.

[#9]

Thanks. I see what you've done but I'm wary of altering things just yet when I suspect the root of the problem is something Greenby have done (or haven't done) in their migration process. Like you, I'm concerned that making changes at my end of things may cause other problems somewhere along the line. I've been with Force9 for 20 years (probably more) and so am cautious about making changes to things I don't understand at this late stage. 

     I'm hoping that someone at Greenby will pick up the problem and either fix it at source or issue a definitive reason and cure for it. It's early days and the hassle of changing my email provider would be enormous but if the change to Greenby looks like being a bag of nails then that's what I'll have to consider.

[#10]

I don't want to speak too soon, but I've just sent two emails without the problem so perhaps someone at Greenby has twisted two wires together (or whatever they do!)

[#11]

It's still not working for me with the force9 version of my address, only with the f9 one. 

The ones sent from f9 go through, the force9 ones no longer generate an error message  - they look like they've sent and show up in the sent folder, but they do not arrive.

Looks like something is shifting. 

Still no migration email from Greenby, though.

[#12]

@janequin 

they look like they've sent and show up in the sent folder, but they do not arrive.

Is it just when sending to gmail or hotmail/outlook/live.co.uk addresses that don't arrive OR is it sending to any address ?

[#13]

@MisterW 

I have so far only tried sending to a gmail address (did not arrive) and to another address on the same force9 email domain I was sending from (did arrive - but not sure if that means anything given they are on the same domain?). 

Is that helpful information?

I have tried a third address but will have to wait for feedback on whether it arrived or not. 

[#14]

@janequin yes, that's helpful.

@plusnettony does that suggest that the force9 domain doesnt have SPF/DKIM whereas the f9 domain does ?

[#15]

You need to “layer” this issue.

Can you send using force9 as the FROM address?

Can you send to the force9 variant of the address?

Seems forece9 and f9 have always been equal aliases within Plusnet, however they are distinct addressing domains.  Both need to have been migrated … or just the variant a user adopted.

EDIT: posts crossing.  Rather doubt that DKIM is implemented.  SPF is easily queried … but not from my phone!