One of my emails isn't sending and receiving via Outlook - please help

Hi, please help me asap. One of my email accounts isn't sending and receiving via Outlook. This is the one I use for my work. This is what it keeps saying: Task 'my email - Sending' reported error (0x80040115) : 'We can't complete this because we can't contact the server right now. Please try again later.' - Please help. Thanks. I posted this job earlier, but the assignee isn't responding and I need this done NOW.