Email failed to send. Check email format is valid

I’m trying to send out some invoices and I’m getting the error message "Email failed to send! Check email format is valid.

I’ve been using my own SMTP settings for a number of months without a problem, the settings have not been changed and are still valid. I’ve checked my email server, there appears to be no problems.

In a previous post there was mention that it was a problem with something on a server somewhere which was reset.

Can this be looked into please,

Just to double check, the email address you’re sending to - is it correct? Have you sent mail to it before without any problems?

This message is a bit ambigious and actually just means the email failed to send, may well be nothing to do with the email format. Are you using your own SMTP server?

I’m using the 3rd party integration SMTP server settings. They are all there, not been touched for months. When I send invoices or anything from quickfile, I get this error message. Not had it before, my email is working fine. I have tested more than one outgoing email address, the error message is displayed regardless of its destination.

There’s something there that your SMTP server doesn’t like.

I have tried to resend your activation email (in the SMTP settings area) as this usually gives a clue to the problem. Your SMTP server at the address provided didn’t respond. You may want to call your email host and just verify if they’ve changed their host address or SMTP port.

I have raised a ticket with the hosting company, its just strange that my email client, using the same settings as quickfile works fine…

We’ve not made any changes here so I can’t say 100%. It could be that they’ve blocked our IP, perhaps they suspected suspicious activity? I think your host will be able to shed more light on this. Do let us know what the outcome is.

Thanks Glen. They have said they very much doubt that they would of blocked quickfile but they are asking for the ip address so that they can check their firewall. Is that something you could provide please?

Yes it’s I checked from another IP and it’s timing out again so I agree it’s not likely to be a blocked IP.

Can you confirm the correct port is 25 and do they support SSL?

Glenn you were spot on. My hosting company didn’t admit that the IP had been blocked but they entered it onto a white list. Surprise surprise, it all now works perfectly. Thanks for your advice and helping me sort this matter out.


Great to hear, it’s always useful to know as I’m sure this will crop up again. Thanks for getting back to us!

I know this is solved now, but I know of a few email problems doing the rounds due to some service providers changing their “Domain-based Message Authentication, Reporting & Conformance” (DMARC) and Sender Policy Framework (SPF) settings.

A brief description and links to more information on email problems can be found here

Hope this is useful, not intended as a shameless plug :slight_smile:

I’m getting the same thing today - all was ok last week, and I don’t think anything has changed.

I think I’m using Quickfile’s own email gateway, but will check…

Hmm, I setup QF to use my gmail account to send, and it seems to be working now.

Hi folks! I’m now getting this error message too. It seems a bit strange that things have been Ok until today. Have there been any chages at QF?

Same here. I want to send invoices but every time I send I get error message as above? Been using QF for a year never had a problem like this before and I have not altered any settings mail or QF side

I’m having the same problem - HELP - NOT HAD THIS BEFORE

I’m using hotmail to send / receive my mail and having the same problem

I am having same problem so have changed back to quickfile sending emails, however am still getting the same error code!

Apologies for the issues here. Unfortunately our email server decided to go down this morning without any warning. We’ve now restarted the email server so it should be fine! We were a bit slow to catch on here with it being a bank holiday.

We’re looking at why this happened and what we can do to mitigate this in future.