You may notice when you're testing the links in your email that one or more of them doesn't work when clicked. When you look at the address bar or the link itself, you may notice that the link has been cut off before the end of the full URL. Why?
Link URLs in your email have a maximum character limit of 255 characters. Most URLs do not come close to this limit, but some links with long titles or added tracking code (Google Analytics code, for example) can run up against this limit. VerticalResponse also adds in its own tracking code so that we can know who clicks the links in your email, and this added code also contributes to your link's character count.
If your URLs are too long and causing the link to "break", try using a link shortening website such as http://bit.ly or http://tinyurl.com to shorten your URL. Paste your full link into these websites, and they will return a much shorter link that you can use in your email.
Want to know how many characters your URL is? Check out http://www.charactercountonline.com/ to get an exact character count.