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Word couldn't send mail due to Mapi failure "unspecified error"

This subjec is cross posted:


I know this question has been asked and "marked" answered several times in the Answer forum, but none of the proposed solutions have worked for me.

I am unable to share/send documents to recipients via e-mail from any installed version of Word on my PC (2003/2007/2010/2013).

(Same goes for Excel 2013, except the error is "General Mail Failure .... ")


I have Window 7 64 bit, Office 2013 32 bit installed. Outlook 2013 is my default mail program. I also have Word 2010, 2007 and 2003 installed. Word 2013 is the default Word application.

In all versions when I attempt to send a document to recipients as an e-mail attachment, I get the subject error. In Word 2003 if I select the option to send to a mail recipient for ("Review") it works without error.

I can also right click documents on my desktop and use the Send to Mail recipient without problems.

I've tried the following:

1. Verified (using several methods) that OUTLOOK is the default mail program.

2. Ran "Repair" on all installed office products (repairing Office 2013 last)

3. Ran fixmapi.exe.

4. Deleted the Office registry settings and repaired all versions again.

5. Uninstalled all versions except Word 2013 and ran repair again.

6. Installed MapiLabs Mail Merge Merge Tookkit (someone indicated this fixed the issue for them)

7. Removed all add-ins from Word and Outlook.

8. I've tried running Word and Outlook as administrator.

9. I've set User Account Control settings to none.

Nothing works. Open to any an all suggestions to resolve. Thanks.


found another proposed solution which suggesting renaming Mapi32.dll to Mapi32Old.dll and then restarting OUTLOOK.

I found Mapi32.dll but when I tried to rename it, I got a notification "You need permission from TrustedIntaller to change this file. Ok, who is TrustedInstaller and how do I let him or her know that my computer in mine (not his or hers) and to please let me decide what I can and cannot do with it?

Frustration is showing here I know. It is a real shame that MS who owns Window, MAPI, and Office cannot get their players together an provide a viable solution to this issue


Question Info

Last updated May 25, 2020 Views 97,914 Applies to:

This issue is finally resolved for me.

This so called "Mapi failure - unspecified error," actually has some specification. Prompted by a tip in another forum, I began searching the Windows event logs for anything related to this issue. I found in the Windows Application event log that Outlook was generating an Error ID 27:

"MAPISendMail: Failed to submit message. Attachments to the message exceeded the size limit set by your Administrator," each time I tried sending an attachment from another office suite application.

Now I had never set a size limit. Not with OUTLOOK 2013 or any earlier version. It appears that the when OUTLOOK 2013 was intalled to replace my earlier OUTLOOK 2010, then the "unlimited' attachment size setting is misread and recorded as "0" size in the OUTLOOK 2013 registry setting.

Changing this registry key: HKEY_Current_User>Software>Microsoft>Office>15.0>Outlook>Preferences>MaximumAttachmentSize from "0" to some larger value e.g., "5000" (5 megabyte) has resolved the issue.

Best Regards,
Greg Maxey

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