Every day, we see emails in our inboxes with fails that are so obvious, it’s clear nobody took a second look before hitting “send.”

A broken link can mean a lost sale: the recipients of your email marketing must be able to access the content you want to share with them, visit your website or buy from your online store. That is why it is very important to verify that all the links in your messages work before sending. Realizing the mistake later will drastically reduce your bottom line.

A newsletter can have many links, from the header that leads to your home page to the call-to-action buttons that encourage the purchase of a specific product, through the images or phrases that are in the text itself. The total amount will vary depending on the type of campaign, but reviewing it can become a slow and complicated task that requires your full attention.

A mistake and, once the message has been sent, there is no way to fix it. Links are essential to get subscribers to leave their email manager and visit you, get to know you, buy you. Adding them is something you should do on your own when you are writing the campaign. Where we can help you is to avoid the time it takes to review them to confirm one by one that they are all correct. This way you will not lose a single customer due to inadvertent carelessness and the statistics of your click-through rate will be reliable.

Email Fail #1: Broken links

Don’t miss out on a conversion opportunity by sending your subscribers to a 404 page or an outdated landing page. The broken link that sent your customers to no-man’s-land is one of the most obvious errors to spot and fix through careful testing.

Unlike URLs in plain-text emails, the URLs in HTML messages usually hide behind hyperlinks within your copy, images, or call-to-action buttons, so they can’t just be checked with a scan of the eye. You’ll have to click each one of them to ensure they’re sending the subscriber to the intended destination—and to ensure that click-throughs are being tracked so you can measure your campaign’s performance.

Email fail #2: Broken dynamic content

Ah, yes–the “Hello, %%first_name%%” fail. Dynamic content is great when it works. When it doesn’t, you look silly, and you’ve lost a great conversion opportunity.

Don’t operate on faith that your data integrations are working in emails with dynamic content. Always test your emails to ensure that your ESP’s merge or personalization tags are working properly and pulling in the correct information. Also, make sure you have a good fallback to cover instances where you are lacking subscriber data.

Email Fail #3: Email not rendering correctly

Every email client, whether it’s a desktop, webmail or mobile version, displays the same email contest a little—or a lot—differently from the others. Plus, email clients can modify or drop their support for HTML and CSS without notifying anyone beforehand. The template that looked so great last week (or yesterday) can be a broken mess today.

Testing your message across different devices and email clients will help you spot and correct rendering issues before you hit send, and ensures that your email looks great and works well everywhere.