Good morning and thank you for posting in the Final Fantasy XI Technical Forums.

As the previous posters may have mentioned, we recommend installing the PlayOnline Viewer from the official website rather than any other method such as Steam. If you were unable to download the PlayOnline Viewer, you may do so using the provided link below:
http://www.playonline.com/ff11us/dow...stall_win.html

Once you have completed the download and installation, please refer to the following link for instructions on how to login and connect to FINAL FANTASY XI: http://www.playonline.com/ff11/manua...?loc=en#900200

Also as previously mentioned, certain legacy drivers must be enabled on your PC for it to start correctly. Please use the following steps to enable these drivers:
-Open the Control Panel
-Open 'Programs'
-Select 'Programs and Options'
-Select 'Turn Windows Features On or Off'
-Open 'Legacy Components'
-Check 'DirectPlay'
-Please relaunch the PlayOnline Viewer after this option has been enabled

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