Excel is showing up the "save as" dialogue in background when custom add-in is enabled in Outlook 2010

Excel is showing up the "save as" dialogue in background when custom add-in is enabled in Outlook 2010

My First question to add-in developer would be, is there any Ribbon designed using Visual Designer in your Add-in?
Said, “Yes” ? Read More…

Visual Designer has issues associated with Outlook. It also causes the ghost Inspector issue.

Following is the steps to Repro:

Create a Outlook2010 Add-in project using VS 2010
Add a ribbon designer in project (Project>Add New Item)
Run the Application
When Outlook Opens, verify that Add-in is loaded (Files>Options>Add-in)
Open Excel
Type "Test"(Dummy text) in any cell and go to File >Save &Send >Send Using Email >Send As Attachment
Outlook Inspector window opens up with attached excel file
Send it to yourself
Go back to Excel
File>Save As
Save As dialogue box goes in background and does not appear even after using ALT+TAB key

Solution:
There are issues with Visual Designer while designing Ribbon in Outlook. Use “Ribbon.Xml” to avoid this issue.

Ribbon Overview(This gives detail on Ribbon Designer and Ribbon XML)
https://msdn.microsoft.com/en-us/library/bb386097

How to: Export a Ribbon from the Ribbon Designer to Ribbon XML
https://msdn.microsoft.com/en-us/library/bb386297

Extending the User Interface in Outlook 2010( Designing Ribbon with Ribbon Xml)
https://msdn.microsoft.com/en-us/library/ee692172.aspx

Happy Coding!

Additional resources