554 mail server errors

I need to send an email to 80 customers.  I put all 80 email addresses in the "Bcc" field in my Outlook 2010, just as I've done in the past with no problem.  But this time when I 'Send', it kicks out all 80 addresses, saying "554 mail server permanently rejected message (#5.3.0)".  I'm hoping someone here can give me some direction so I don't waste a lot of time searching for a solution in the wrong place.

Could this be caused by my email provider, which is Network Solutions?  Or could it be caused by a setting in Outlook, or something about Windows 10 Pro?  I can't imagine it is a problem at the customer level, since all 80 are kicking out immediately.  

I did send two of them out individually, and that worked fine.  I don't want to test it by putting all 80 email addresses in the normal "To" field, because that's the whole reason I'm trying to use the "Bcc" field.
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

David Johnson, CD, MVPOwnerCommented:
your mail server thinks it is spam.. any attachments?
timgreen7077Exchange EngineerCommented:
This is most likely something with the mail provider and not the outlook client. Error code 5.3.0 is defined as the following:

5.3.0 Problem with MTA, maybe someone has been editing the registry to disable the MTA / Store driver.

So this indicates that there is an issue with the mail server sending that message so you will most likely need to contact your providers.
Unfortunately it could be one of number of reasons.
  1. For some reason your smtp server is actually blocking you, usually due to having you on some black list or marked as spammer. solution contact your smtp admin.
  2. You have an attachment in your email and your server "thinks" its either a spam \ virus or something of that kind. In this case I would try to zip the file and re-send everything.
  3. There is a policy limiting the number of addresses in a single outgoing message. In this case the solution is to either follow the servers policy as to the max number of receivers or to contact the admin and ask to have a higher max limit.
These are the most common reasons I can think of at the moment.
Hope this helps.

Best of luck.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Alexei KuznetsovMicrosoft Outlook MVPCommented:
Just use specialized solution for this. Like Word MailMerge: it will create a separate message for each of the recipients.
sasllcAuthor Commented:
Based on helpful suggestions here, I called Network Solutions and found that there was a maximum of 100 emails that could be sent out at one time.  I counted them and found that I had 102, so I split it into two emails and then it went fine.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.