If you've been hijacked, you first need to work out how. This is because if you ignore the possibilities, you could just get hijacked again and lose any progress you make in the future.
Look at one of the following sections depending on which is relevant to you.
Download at least one of the recommended security programs (those classed as an antivirus or antimalware application) and run a full scan with it.
AFTER the scans are done (it must be after, or any potential keyloggers will re-steal your information) check if you have access to your registered email still. Assuming you don't...
1) You've likely used the same pass.word for RuneScape and your EMail (in which case, make a new email and use a new pass.word!)
2) You may have malware on your computer.
If you do have access to your registered email, you need to check if your account is still linked and recoverable. View this thread and attempt to lock your account.
If you do not recieve an email within 30 minutes, your account is probably stolen and the email has been changed. It is also possible that you are not recieving mail from Jagex, but that is also covered here, as is where to go if the email is changed by a hijacker or stolen.
If the scans are clean, you haven't reused pass.words and you've been a silly person or haven't been phished, you may have been targeted by a hijacker. You can recover your account through the 3rd option on the locking guide in my signature. Read page 1 of this thread before proceeding! Boot/Lock account repost | Comprehensive Account Security
JAG is superior to Authenticator
31-May-2015 04:26:44 - Last edited on 24-Jan-2016 18:15:25 by Salubrious