I am making custom masterpage for sharepoint. In the beginning no problem until I add script for using javascript. There is javascript error on left bottom corner of browser, theForm’ is undefined’. It makes me pretty confused.

I need google for helping this and give me some solution. As it turns out, It is because the v4.master does not like self-closing JavaScript tags.

Solution: The < script > tag I had this tag placed on master page like this < script / >,  changed it to < script >< /script >

Change this:
<script type=”text/javascript” src=”../../Style Library/en-us/Scripts/jquery.js”  />

To this:
<script type=”text/javascript” src=”../../Style Library/en-us/Scripts/jquery.js” ></script>

Reference:

http://www.sharepoint-bytes.com/2011/10/theform-is-undefined.html
http://iturbandictionary.com/Susan/Lists/Posts/Post.aspx?ID=20
http://michaelhanna.me/2010/11/14/javascript-error-while-approve-masterpage-sharepoint-2010/