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IT solutions: Email attachment size limits, file-upload time

Have you ever wondered if you were the only person on campus with a particular computer problem? Got a quick technology question and don’t know who to call? Contact the IT Help Desk, 785-532-7722, e-mail helpdesk@k-state.edu.

Next topic:How to share files that are too large to attach to emails

Question:  I am trying to send an attachment to my email in Zimbra webmail. What is the limit on the file size?

IT Help Desk:  The limit for each email in K-State’s Zimbra system is 50MB (megabytes) including attachments.  That’s 51,200KB (kilobytes); 1 megabyte = 1,024 kilobytes. That is substantially more than most email service providers allow (typically 10-25MB).  So, when you are considering sending a large file attachment, first check the file size.

This does not take into consideration that a file attachment needs to be encoded — which typically adds roughly 30 percent to the file size.  That means the upper limit for a file attachment(s) is closer to 35MB.  It depends on the content of the attachment.

Next, you need to confirm the size limit of the recipient’s service provider, i.e. Gmail, Yahoo, or Hotmail.  For example, you have a 31MB, 45-minute audio file (.mp4).  Although a file of this type can be sent as an attachment from Zimbra webmail, it exceeds the size limit of the Gmail server.  Therefore, it cannot be accepted by a Gmail client, and it will be returned as undelivered mail.  However, you should have no problems emailing the file to another K-State account.

Question:  If I want to send several files, does it matter if I attach them all in one email or send them separately?

IT Help Desk:  Email attachments are a fast, simple method of sharing smaller files or one file at a time. You may want to consider splitting multiple files into individual emails, especially if one of the files is large. See the first question above, about the total 50MB limit for each email.  (The next article will consider alternative methods for sharing large files, such as for group projects, portfolios, and theses and dissertations.)

Question:  I am attaching a video file in Zimbra webmail, but it takes forever to upload the file. How long should I wait before I cancel the upload process and try again?

IT Help Desk:  If you have first checked the file size and confirmed that it is not over the size limit of 50MB, you can estimate the typical time for the file to upload. The upload time can vary, depending upon several factors such as your computer’s processor, your Internet connection, and the file size.  Don’t panic if it takes a few minutes for a large file; the bigger it is, the longer it takes.

For more information

Consider reading the article “Problems Attaching Files Through Email” by  eHow contributor, Diana O’gilvie.

by Deborah Goins, IT Help Desk consultant