Can't play two Steam instances anymore...

Try running one steam instance in offline mode, or disable internet for it through

sandbox setting - restrictions - internet access

Thanks for your response, but, Steam will not start with internet restrictions...

Also, I can't find how to run Steam offline, could you please tell me the steps?

maybe you need to change the settings in sandboxie. there's a step where you're supposed to make steam run in some special way:

open sandboxie > make a new sandbox> name it steam or something obvious > right click on its icon > settings > click + on Resource Access > File Access > Direct Access > Add Program > "Open / Select File" > (find steam , probably located at C:\Program Files (x86)\Steam\Steam.exe) > select it in the filebrowser (click open) > hit ok a few times > right click on the sandboxie icon you made > "Run Sandboxed" > "Run Any Program" > find steam again and launch it

(or you can listen to a 13 year old british kid explaining that if thats how you like doing things https://www.youtube.com/watch?v=heW1Xzttz1k)

i never had the problem you had, hopefully that settings change was enough to fix your problem.

i have the same setup:

>windows 10 home

>1 pc, 2 monitors, 

>using aster, sandboxie;

1) main pc terminal runs steam with sandboxie on steam account A

2) secondary pc terminal runs steam normally on steam account B

2.5) i did have an unmentioned problem where the sandboxie steam had like a black screen for everything, but that is fixed by going to program files > sandboxie and changing all of the .exe's in there to be ran as administrator (properties>compatibility>check the box "run this program as an administrator"). after that, you have to find the .exe of every game you wanna play and do the same to that.

3) it works

4) i tested same thing except this time both terminals use steam account A

5) opened "the resistance" on one and csgo on the other

6) close largely meaningless sandboxie error messages

7) it works

8) turns out changing the game's .exe to be admin is not required for all games

are u sure youre running the steam in sandbox mode? i didnt have your problem at all

maybe you need to change the settings in sandboxie. there's a step where you're supposed to make steam run in some special way:

open sandboxie > make a new sandbox> name it steam or something obvious > right click on its icon > settings > click + on Resource Access > File Access > Direct Access > Add Program > "Open / Select File" > (find steam , probably located at C:\Program Files (x86)\Steam\Steam.exe) > select it in the filebrowser (click open) > hit ok a few times > right click on the sandboxie icon you made > "Run Sandboxed" > "Run Any Program" > find steam again and launch it

(or you can listen to a 13 year old british kid explaining that if thats how you like doing things https://www.youtube.com/watch?v=heW1Xzttz1k)

i never had the problem you had, hopefully that settings change was enough to fix your problem.

i have the same setup:

>windows 10 home

>1 pc, 2 monitors, 

>using aster, sandboxie;

1) main pc terminal runs steam with sandboxie on steam account A

2) secondary pc terminal runs steam normally on steam account B

2.5) i did have an unmentioned problem where the sandboxie steam had like a black screen for everything, but that is fixed by going to program files > sandboxie and changing all of the .exe's in there to be ran as administrator (properties>compatibility>check the box "run this program as an administrator"). after that, you have to find the .exe of every game you wanna play and do the same to that.

3) it works

4) i tested same thing except this time both terminals use steam account A

5) opened "the resistance" on one and csgo on the other

6) close largely meaningless sandboxie error messages

7) it works

8) turns out changing the game's .exe to be admin is not required for all games

are u sure youre running the steam in sandbox mode? i didnt have your problem at all