my macbook wont sleep anymore

Create a new user account. Log into this new account. Test if the problem has ceased. If it has then you have a problem in your Home folder that is preventing sleep. This could a corrupted preference file, cache file, or document file. It could be caused by a bad plug-in such as a preference pane.

What version of OS X are you running? Did you install the recent Java updates for your system?

jesse_obert wrote:

I am currently running Java 6se

Kappy asked if you ran "Java for Mac OS X 10.6 Update 13" released on Tuesday? Previous versions of Java have been disabled for browser use.

The latest "...update will configure web browsers to not automatically run Java applets. Java applets may be re-enabled by clicking the region labeled "Inactive plug-in" on a web page. If no applets have been run for an extended period of time, the Java web plug-in will deactivate."

Are all three check boxes in Java Preferences checked?

I realize the above is the old version, but it's all I have at the moment.

Have you read this How to use Java if it's been blocked?

It's not going to be in Mountain Lion. In Safari you can look under Security to make sure Java is enabled and then go to Help/Installed Plug-Ins and see if build .41 is listed for Java at the top.

Honestly, if you have ML, you might as well load up the new version 7 of Java off java.com and try that. It's not exactly any better, but you'll at least get a System Preferences icon to control things via.

Generally speaking Java 7 works better with FireFox than Safari... from what I've experienced.

jesse_obert wrote:

How do i get to the above screen?

/Applications/Utilities/Java Preferences.

SwankPeRFection wrote:

It's not going to be in Mountain Lion.

OP is running Snow Leopard.

Then the old school Java console should be available to them.

jesse_obert wrote:

My computer is onnce again not sleeping when I close the screen.

I'm just here for Java, so if it's working now I'll step aside.