How to open .IDX255 file extension?

If you cannot open a new file that has been saved in the .IDX255 format you need to download the appropriate software. The manufacturer of .IDX255 files is Jagex; .IDX255 files belong to the Game Files category. After downloading the application from the list available on our website just run an unknown file, and as the default set the newly installed application supporting the .IDX255 files. Activities performed in the order described should solve the problems with all the files in the .IDX255 format.

• What is .IDX255 file?
• How to open .IDX255 file?
• What is .IDX255 file?