In some email clients the link for your account registration verification may be split into several distinct lines instead of one line that just wraps at the end, i.e. as a continuing sentence.  When this occurs, clicking the link to verify will only use the first line of the link and therefore fail its verification.  To overcome this, copy all lines of the verification link to a text editor and join them together as a single line.  Then copy and paste that single line into your browser address bar.  You registration verification should then proceed.

For example, if your verification link is displayed like this, i.e. with only the first line your "link" colour, then you will need to copy all lines, join them together, and then paste them into your browser address bar.