Date formats in MySQL are not the same as they are in MS SQL or Access. In MySQL, by default, dates are in this format: yyyymmdd. In order to handle this in .Net you need to format your dates using a String.Format function like this:

String.Format("{0:yyyyMMdd}", now)

This will give you the date in the format that is accepted by MySQL. You may also add '/' or '-' to your dates without any errors, like this:

String.Format("{0:yyyy/MM/dd}", now)

or

String.Format("{0:yyyy-MM-dd}", now)

Anything other than those two characters and you'll get an error from MySQL.