Are you using some account provided by your ISP? Looks like there is a restriction at the server side to not to receive attachments(or emails with more than certain size). This might be the reason your emails are not going.
To know the exact problem, try the below.
Send a email with photo attachment and verify that it still stays in outlook.
In your outlook click on the button send/receive and let the receive fail
After the fail, just note the error message displayed in "send/receive" window.
This clearly explains where the problem is.