# Help choosing a module **URL:** \ **Category:** General Discussion\ **Created:** [January 23, 2018, 7:12pm UTC](https://forum.vassalengine.org/t/help-choosing-a-module/9244 "2018-01-23T19:12:20Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![banane42](https://forum.vassalengine.org/letter_avatar_proxy/v4/letter/b/f9ae1b/32.png) [@banane42](https://forum.vassalengine.org/u/banane42)\ **Post date:** [January 23, 2018, 7:12pm UTC](https://forum.vassalengine.org/t/help-choosing-a-module/9244/1 "2018-01-23T19:12:20Z")
Hello everyone, I am new to Vassal as I just discovered it existed today. As part of a class I am taking my professor sent us a .vlog file as a challenge for extra credit. After some googling I found Vassal which recognized the file. However I am having a hard time opening the file as I get the “file not a valid vassal module” error message when trying to open it as a module. I suspect that I need to proper module before I open the file itself. Any help would be greatly appreciated. ---
**Author:** ![Malnorma](https://forum.vassalengine.org/letter_avatar_proxy/v4/letter/m/22d042/32.png) [@Malnorma](https://forum.vassalengine.org/u/Malnorma)\ **Post date:** [January 26, 2018, 7:59pm UTC](https://forum.vassalengine.org/t/help-choosing-a-module/9244/2 "2018-01-26T19:59:05Z")
Just having a .vlog extension doesn’t mean the file is actually a vassal file. Take a look at the content of the file by opening it with a simple text editor (say, notepad on Windows). You may be able to read the contents, or spot something in there that gives you a clue about the file. Vassal vlog files are actually just zip files, and zip files begin with “PK” as a signature. If you see PK at the start, you can rename the file to .zip and open it to see what’s inside. If it’s a Vassal file after all, you’ll see a file called moduledata, and that will tell you the name and version of the module it applies to. Good luck!