When passing information via URL variables, we have to be careful that those variables do not contain non-URL-friendly characters. This includes spaces and non-alpha-numeric characters…
to be able to pass this characters, you have to first convert it to URL-safe hexadecimal escape characters…

And to do that, just use the URL encode function..

In classic Asp and Asp.Net:
Server.UrlEncode()

In classic PHP:
urlencode()

In classic Coldfusion:
URLEncodedFormat()