I de-cluttered my computer & now i can't access some web pages?

Your Registry is corrupted...The only way to fix this is REMOVE the application which you installed... Reboot then install this software named CCLEANER here download.cnet.com/ccleaner/

the troble may not be just your computer some web pages have going to formats many older computers can not read Myspace and now Twitter are such pages new pugins and other things that don,t make it into an older computer and your program may have taken some needed out as well little patch programs your computer had to see things that got tossed as trash

This is why people shouldn't use pre-made programs to "de clutter" their computers. Sounds like it broke Java, Flash, or some other plugin. Adobe maybe? Hm. Not really sure what plugin Facebook uses to enable messaging. What exact program did you use? That could narrow down the possibilities.

The clean up program should have an undo. Try that but be sure what you used is NOT malware. Search for its reputation before you do much of anything. A previous poster suggested reinstalling JAVA. Get it here: http://www.java.com/en/download/manual.jsp. If you have a Widows machine, get all the Microsoft patches here: http://update.microsoft.com/windowsupdate/v6/default.aspx?ln=en-us. Registry cleaners work but there is a learning curve and and some are rogues. I suggest you stick with Avanquest, Norton, WinZip (NicoMack) or the one that comes with McAfee.