Have check your website to see if it works ok with your host? your server needs to support php 5.x in order to work with x5 form mail and guest book.

go to your  www.yourdomain.com/admin and log in, then go to test tab and see if you have the 3 green bars over there. this is the first step for troubleshooting your guest book.

if this post is the correct answer, please mark this answer as correct answer.

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Good Luck
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