Increase the attachment's size in Exchange 2016

Dear guys, we have an Exchange 2016 on-premise server and would like to increase the attachment's size of users' emails to 100 MB. We did some research and followed but still got the error "The following files weren't attached because adding them would cause the message to exceed the maximum size limit of 25 MB: smex_12.0_ag.pdf. " when attached a file that is bigger than 25 MB into an email. Could you please suggest?

Attached pictures are our settings, we restarted IIS, Transport services, even server itself but did not help!
DP230Network AdministratorAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

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.

John TsioumprisSoftware & Systems EngineerCommented:
Have you checked if your Transport is limiting you....check the Ms guideline
Scott CSenior EngineerCommented:
Take a look at these two links, the first article is from MS and the blog is from CodeTwo.

These should tell you what you need and how to increase it.
SeanSystem EngineerCommented:
While you can change this on the transport I'll tell you if you send outside of the org they will get blocked. Usually most email servers will not accept most messages that are larger than 25-30 mb in size. But again if you are receiving that large email or doing so internally that will be just fine.

get-transportconfig | Set-TransportConfig -MaxSendSize 100MB -MaxReceiveSize 100MB
Simplify Active Directory Administration

Administration of Active Directory does not have to be hard.  Too often what should be a simple task is made more difficult than it needs to be.The solution?  Hyena from SystemTools Software.  With ease-of-use as well as powerful importing and bulk updating capabilities.

DP230Network AdministratorAuthor Commented:
Did you see my attached pics, I followed your links before asking this question, but did not help
Pete LongTechnical ConsultantCommented:
Come on guys, instead of trying to be first to post, read the question :(

You look to be setup correctly, and as you have bounced the server the AppPools will have been restarted/recycled (just in case people are still Googling!)

I'm assuming this is a stand alone server? If you open the web.config files (one for EWS and One for OWA) do they match the settings the connecters are telling you they are using in the Shell?

or it might be
%ExchangeInstallPath%ClientAccess\owa\web.config - I dont have access to one to check at them moment.

Also make sure nothing is doing ESMTP inspection between the clients and the Exchange server, (again assuming you are on the same LAN and not connected via https)


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
Pete LongTechnical ConsultantCommented:
Actually if you are connected via HTTPS then see this article, notice the Active-Sync size limits are defined differently!

DP230Network AdministratorAuthor Commented:
@Peter: Thank you very much, it worked perfectly :)

@others: please read the question before answering, become first post is not guaranteed 1000 points!
Pete LongTechnical ConsultantCommented:

Cheers, to add a little more weight to the question, I wrote this today.
Exchange : ‘Message Exceeded The Maximum Size Limit’

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.