For more information read the FAQ:
Problem: The online game doesn't load or stays on a gray screen.
Solution: 1. Make sure java is turned on.
2. Close the game window and reload the browser window. Then, try to play again.
3. Quit browser then restart it.
4. Clear "temporary internet cache."
5. Make sure you have the latest update for your browser.
6. Make sure you have the latest java from www.sun.com/downloads
7. Try switching browsers.
Problem: The windows client doesn't work/gives me an error message.
Solution: Delete the file and re-download it.
Problem: My FPS (Frames Per Second rate) is 4, can I raise my speed?
Solution: 1. Press F1 one time while playing the game.
2. This one is for Windows users and only works if you used to get high fps, but now get only 4fps:
Make sure your Java Virtual Machine is turned on!
In Ineternet Explorer go to "tools" menu ---> advanced tab ----> microsoft VM. Make sure "Java Console Enabled" and "JIT compiler for virtual machine" are checked. Leave the middle option unchecked.
Problem: I am experiencing frequent disconnects.
Solution: Get off runescape for 5 minutes and restart the internet in a new browser window.
The most reliable way to play RuneScape on a Macintosh is to use Netscape 4.77.
Problem: The game loads on Internet Explorer but I can't type anything into the login boxes.
Solution: RuneScape requires at least 50megabytes of RAM. You may need to allocate more RAM to the Internet Explorer application (click on the application, press command-i, and choose "memory").