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  • Writer's pictureStan Patey

Message Size Limit Exceeded – What Now?

It’s late on a sunny Friday afternoon before a long weekend and the office has emptied out around you. You’ve worked frantically to complete a multi-media project that you promised to send over to your client for review before the end of the day. The crafted email message is complete, then you attempt to attach the documents only to be derailed by “The file you’re attaching is bigger than the server allows.”

The file you're attaching is bigger than the server allows.

Documents, spreadsheets and presentations that exceed the typical 25 MB size limits of major email hosts are growing more common. Despite increased limits, it’s easy to hit the max.

Oversize Load Truck Image

Even a 20 MB attachment can push your email beyond size restrictions due to the encoding overhead necessary to attach to an email message. In some instances, an email with a 20 MB attachment can swell to 30 MB’s.

Office 365 limits message sizes to 25 MB's but system administrators can modify it to allow up to a 150 MB limit. That's pretty much pointless when the vast majority of non-Microsoft email providers set their ceiling at 25 MB's. What good is it if you can send it but no one can receive it?


Common error messages for emails that get blocked due to exceeding size limits include

  • 552 5.3.4 message size limit exceeded

  • System Undeliverable, message size exceeds outgoing message size limit.

  • Unable to send email: Message size exceeds server limit

  • Mail Delivery Failed: message size exceeds fixed maximum size

  • The size of the message you are trying to send exceeds the global size limit of the server. The message was not sent; reduce the message size and try again.

  • Attachment size exceeds the allowable limit



  • Reduce file size by compressing into a zip file. In File Explorer select the file or files then right-click>Send To>Compressed (zipped) Folder

  • Divide files into two or more smaller files then send in multiple emails

  • PDF’s can be reduced in size within the Adobe Acrobat application - File>Save As Other>Reduced Size PDF

Use a file sharing service.


There are several familiar file sharing services including Dropbox, Google Drive and Microsoft’s OneDrive that offer excellent solutions but require downloads and configuration. Dropbox fees can quickly climb for both the sender and recipient. Google Drive includes 15 GB’s of storage on their free tier and is accessible for Gmail users. Microsoft OneDrive is fabulous once you get it configured and learn how to share links with recipients.

But, when it’s late on Friday and you just want to get that file transferred consider one of these free transfer services. They allow file transfer sizes from 2 to 8 GB’s on their free tiers, don’t require any software downloads or configuration and are quick and easy to use. Simply browse to their website, enter the sending and receiving email addresses then add your files and click send. The files upload then your recipient will get an email with a link to allow him to download the files.

pCloud Transfer notification email

Check out these file transfer service solution

WeTransfer – Send up to 2 GB’s / No Registration / Free pCloud Transfer – Send up to 5 GB’s / No registration / Free WeSendit - Send up to 5 GB’s / No registration / Free DropSend - Send up to 8 GB’s / No registration / Free

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