How To Solo The Past Within (Steam, PC)

Need to run two instances of The Past Within on one computer? Here's how. 

Credit: I am copying most of this directly from Acen's guide "Run 2 Accounts on One Computer". This method worked with The Past Within at the time this blog was published. 

For your own sake, READ THE ENTIRE GUIDE BEFORE TAKING ANY STEPS.

Requirements 

1 Steam account 

1 copy of The Past Within installed on your computer

Sandboxie-Plus (setup guide below)

1. Folder Setup and Game Copy (optional)

Creating a new folder and copying the game files over is typically recommended but you can use the existing folder to save space if needed. Skip to next section if you want to use your current folder.

Open up your Program Files directory where your Steam installation is (eg, C:\Program Files (x86)\)

Create a new folder, I named mine "SteamSand" to make it simple.

Now go into your normal Steam folder (eg, C:\Program Files (x86)\Steam\)

Copy the folder "SteamApps" and file "Steam.exe" and Paste them into your SteamSand folder (eg, C:\Program Files (x86)\SteamSand\)

Remember to COPY&PASTE, Do not MOVE. This can take a while depending on how many games you have installed. If you only want The Past Within, DON'T copy the entire SteamApps/Common folder, only Common/The Past Within.

2. Sandboxie Setup

Now, Download Sandboxie-Plus from their website sandboxie-plus.com

Install and Run Sandboxie-Plus. If you chose Sandboxie-Classic, follow Acen's guide from here on.

Configure the settings to your liking. I went for simple and dark UI.

When it's open, At the top click "Sandbox" and "Create New Box"

Choose Standard Isolation Sandbox (Default) and name it whatever you want. I named mine "Steam". Then Click OK

Once you've clicked OK, You'll see the new sandbox appear in the list, Right click on it and click "Sandbox Options"

In Options, navigate to "Resource Access" and click the arrow next to Add File/Folder. Choose Folder. 

Browse to your Steam or SteamSand folder. Click on the folder and Click OK.

Click Apply and then OK

3. How to Run 

Now go back to your Steam or SteamSand folder, Right click on "Steam.exe" and click "Run Sandboxed"

You'll get a popup which will have you choose which Sandbox to run it with. Click on your "Steam" sandbox and click OK. (You may need to select the UAC check box as well)

Steam will now open and probably prompt you to Login. 

If you completed Step 1, Steam will automatically download all the missing files we didn't copy.

Done!

Note: It is best to create a shortcut on your desktop to the "Steam.exe" file in your "SteamSand" folder and name it something like "Steam - Sandbox" as you will ALWAYS have to Right click -> Run Sandboxed.

4. Starting The Past Within

Now that you have Steam running on both Sandboxie and your desktop, set one or both of these to Offline mode. 

Launch the game from your main Steam. Turn the full screen mode off. 

Launch the game from Sandboxie Steam. 

Do whatever you need to make switching between two windows most comfortable for you.

Congrats, you're ready to solo The Past Within.

! Important Notes !

Don't count on your progress being saved!

Any achievements gained in offline mode may not register on Steam.