Reasons won't your PDF files open in your email:

• a file that is corrupt-It's also possible that the attachment you received is corrupt if none of the suggestions above helped you figure out or solve the problem. Reply to the e-mail with a request for the sender to check the attachment on their computer and to send a fresh e-mail with a new attachment.
• Antivirus software protects you against viruses.-If you have an antivirus protection product installed on your computer, briefly disable it to see if it's causing issues with your attachments.
• You have a PC and Sender has an Apple machine.-You may be unable to open an attachment if the e-mail sender uses a Mac computer and the attached files were not saved in a Windows-compatible format. If an attachment is being sent to you, make sure the sender is aware that you are using Windows.
• File in compressed format-When sending multiple files via e-mail, it's common practise to combine all of the files into a single compressed file and attach it to the e-mail. If the file is compressed (.zip,.rar, or another format), it must first be decompress before it can be opened.

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