could be you have it installed – but is corrupt – try repaing from tools – manage addins – could also be an issue with your internet security being too high – checkout tools – internet options – advanced – look for java settings and if they are ticked until – if they are unticked ticked – sounds a bit odd but this does work

there are a couple of ways the two most basic are server side includes and php includes some servers do not support one or the other depending on how the server was set up and what is installed so first thing to do is isolate the code that you want to reappear in multiple pages and then save that to a new html file next if you use php includes your files that you want this page to be included in must have the .php file extension which just means that its an html page that can support php scripts as long as the server can as well. to include the file simply type
<?php include("file_name"); ?>
where you want the code to be inserted on the page
for server side includes again copy the code to a new file however if the file is just html save with .shtml extension if it is an asp or php page than save with appropriate extension. the file type of the page that has the include statement can be html or php or any number of web page file extensions just put the following line in where you want the code to be
<!–#include virtual="file_name" –>