Below is a listing of all of the different reasons why you may be unable to open an e-mail attachment.

Note: This document is for people who have received an attachment in an e-mail but cannot open it. If the attachment is missing or not available see our I can't receive any e-mail attachments page.

Unrecognized file format

One of the most common reasons why you may not be able to open an e-mail attachment is because your computer does not have the necessary program installed to recognize the file format. For example, if someone is sending you a .PSD image file and you do not have Adobe Photoshop or another program that supports that file format it cannot be opened.

In this situation, we recommend you have the sender save the file as a different format that your computer supports and re-send the attachment as that file format. If you believe you are going to be working with this type of file format often, you should install a program or a viewer on the computer that supports the file format. Below is a listing of some of the more common file formats send over e-mail, their file extension, and the programs used to open those files.

File typeExtensionDescription
Document.doc or .docxMicrosoft Word documents and can be opened with Microsoft Word, OpenOffice Writer, or Google Docs.
PDF.pdfAdobe PDF file that is opened with Adobe Acrobat or other PDF reader.
Spreadsheet.xls or .xlsxMicrosoft Excel spreadsheet that can be opened with Microsoft Excel, OpenOffice Calc, or Google Sheets.
Basic Image.gif, .jpg, .jpeg, .pngThese basic image formats are widely used and can be opened and viewed by every image editor or viewer.
Compressed, .rar, .zA compressed file that must be uncompressed before the files contained within the file can be viewed.
Bitmap.bmpWindows Bitmap image that is primarily opened in Microsoft Paint and can be opened with many but not all image editors.
Movie.avi, .mov, .wmv, .mp4, .mpegMovie files that require a compatible media player program to play.
Audio.mp3MP3 audio file.
Executable.exe, .comAn executable file that starts the installation of a program. Be cautious of any executable being sent through e-mail as this is the primary method of distributing viruses through e-mail.
HTML.html, .htmHTML file. For example, a web page may be sent as an attachment in e-mail.

Bad file association or problem with program

If the file format is something your computer should be capable of opening but is encountering an error or other problem when its being opened, it is possible that the file format has been associated with the wrong program or the program used to open that type of file has problems.

For example, let's say you want to view a PDFdocument. Many modern web browsers offer their own PDF viewer, but this PDF is an attachment sent in an email from a trusted sender. However, you don't have a PDF viewer such as Acrobat installed.

Instead of trying to open the attachment directly from your e-mail client, save the attachment to your computer (e.g., save it to your Desktop). Then, right-click the file and under Open With, choose a different program to open the file. If this works and you would like the program to always open this type of file, right-click the file and under Open with, choose another app. Check the box Always use this app to open and select the program you want to use and click Ok.

Compressed file

When needing to send multiple files over e-mail, it is not uncommon to compress all of the files into a single compressed file and attach that compressed file to the e-mail. If the file is a .zip, .rar, or other compressed file formats, you must save the file to the computer and then uncompress the files before they can be opened.

Antivirus program preventing

If you have an antivirus protection program installed on your computer, make sure it is not causing problems with your attachments by temporarily disabling your antivirus.

Sender has an Apple computer and you have a PC

If the e-mail sender is using a Mac computer, but their attached files have not been saved in a Windows-compatible format, you may be unable to open the attachment. Make sure that the sender of the e-mail knows that you are using Windows if they are sending you an attachment.

Outlook Add-ins

If you are using Microsoft Outlook and unable to open attachments, make sure an Add-in is not causing the problem. You can disable all Add-ins in Outlook by following the steps below.

  1. Open Microsoft Outlook.
  2. Click File, Options, and then Add-ins
  3. Under Manage click COM Add-ins.
  4. Click on GO button next to Manage and then uncheck all of the add-ins.
  5. Once everything has been disabled, click Ok.
  6. Close Microsoft Outlook and then re-open Outlook to see if the attachment issue has been resolved.

Corrupt file

If none of the above suggestions helped determine or fix the problem, it is also possible that the attachment you received is corrupt. Reply to the e-mail asking the sender to verify the attachment works on their computer and to create a new e-mail and attachment.