Hi, I have a tutorial and it is in .og extension. My windows media player is not playing this. It is saying that codex might not be supported although file type is, I am not sure what to do in this case. Any suggestions my IT friends? Hina. This email and any attached files are confidential and intended solely for the intended recipient(s). If you are not the named recipient you should not read, distribute, copy or alter this email. Please notify the sender immediately via email if you have received this email by mistake, then delete this email from your system. Any views or opinions expressed in this email are those of the author and do not represent those of the Center for Sight & Hearing. The Center does not accept liability for the content in this email or for the results of actions taken based on the information provided unless that information is confirmed in writing. Warning: Computer viruses can be transmitted through email. The recipient should verify this email and any attachments for viruses. Although precautions have been taken to make sure no viruses are present in this email, the Center does not accept responsibility for any loss or damage that arises from the use of this email or attachments.