I also have this problem. Somethings I have noticed that may or may not help at all: 1 the line "XalPlatform_gamecore.cpp(80)] Store State : NotMatched - Account detected" shows up in all three launcher logs and mine however mine says 85 instead of 80 2 the line "LauncherController.cpp(1398)] Windows Store Launcher is NotSupported" also shows up in all three logs and mine and again mine number is different. 1398 vs 1406 3 using the alternate download https://www.minecraft.net/en-us/download/alternative for windows 7/8 does not give me the error mentioned above but I still can not play online.
Yetifur
I also have this problem. Somethings I have noticed that may or may not help at all:
1 the line "XalPlatform_gamecore.cpp(80)] Store State : NotMatched - Account detected" shows up in all three launcher logs and mine however mine says 85 instead of 80
2 the line "LauncherController.cpp(1398)] Windows Store Launcher is NotSupported" also shows up in all three logs and mine and again mine number is different. 1398 vs 1406
3 using the alternate download https://www.minecraft.net/en-us/download/alternative for windows 7/8 does not give me the error mentioned above but I still can not play online.