*.83g or *.8xg are grouped calculator files. These grouped calculator files work almost like *.zip files. All they do is combine calculator files into one big file. Usually most people have a problem with these becaue they try to open them. Let me tell you right now that you CANNOT open *.83g/*.8xg files by going to File and Open. If all you want to do is send the contents of the "packaged" file to your calculator, just send it like you normally would. However, if you want to view the calculator program files (*.83p or *.8xp), then you will have to ungroup the grouped file. To ungroup a grouped file go to Tools and choose Ungroup. If you're using the TI-83 Plus Graph Link software, then you'll have a choice of ungrouping TI-83 Files or TI-83 Plus Files. Next, find the folder that the grouped file is in. After double-clicking on the grouped file, another window will appear asking for the target directory. The target directory is where you want the files inside the grouped file to be placed. The default is the folder where the grouped file was. Finally, a window will appear showing you all the files that are being ungrouped. Once that is finished, click OK and you're through.