Have been using Vassal on a Mac desktop successfully for years. Also on a MacBook (my wife’s). My wife recently started disallowing me to take her MacBook when I travel, so I bought an inexpensive Windows laptop for Vassal.
Installation went fine, but evidently I did something wrong the first time I was asked for my name and password. I’m in the middle of a game of Axis Empires/TK! and when I loaded the log file on the laptop, I was not allowed to join as my “side” (Western). I was offered observer, Axis, Japanese, and referee.
I went back to the Mac desktop, successfully loaded the same file, retired, and then saved the file again. Again I loaded it on the laptop, and this time I could choose to log in as Western – but when I saved THAT file, I could not log in as Western on the Mac!
I uninstalled Vassal on the laptop, re-installed it, and now I’m back to not being able to log in as Western on the laptop. I noticed that I was not asked for a name or password after the reinstallation.
This is an indication that the module password you entered on the borrowed laptop differs from the module password in use on your Mac.
Good instinct so far…
Still back on the root problem here–the module password differs on the two computers. It must be identical on all computers you intended to use for a given game.
This is normal. You are only prompted to select a username/password the very first time you open a given module on a computer. Subsequently you can change it by opening the module, declining to start or load a game, and going into the Preferences and then the Personal tab. Uninstalling VASSAL will have no bearing on the per-module preferences that are created in your user directory–they remain.
The location of the VASSAL preferences on Windows is: C:\Users*your username here*\AppData\Roaming\VASSAL\prefs. On MacOS, it is: ~/Library/Application Support/VASSAL/prefs. There are a bunch of plain text files in here that will show you the module password currently stored for each module, if you’ve forgotten.
My recommendation in your situation would be to take your game file, retire again and save it (thus occupying no player side at all). Then open the module on each computer and ensure that the module password is the same on BOTH computers. Then you should be able to load your file, select a side, and be slotted into that side on both computers.
Unfortunately it’s a hideously designed system in this regard and very obnoxious to recover from the situation you’re in, nor does it warn you about how to avoid it. But it’s not changing until the application is rebuilt from the ground up.