Using Multiple Excel Instances with DecisionTools Suite

 

Can I open a workbook without DTS in the ribbon?
Yes. You can open a second instance of Excel to work on a workbook while @RISK, Evolver, or other DTS tools run in the first instance. In this second Excel instance, do not run any DTS software. If the workbook contains @RISK functions, they show as #NAME, but you can edit formulas in the formula bar or copy/paste them.

What’s the difference between a second workbook and a second instance?
Opening a second workbook opens it in the same Excel instance; Task Manager shows one Excel process. Opening a second instance loads a fresh Excel process; Task Manager shows two. DTS software cannot run in a second instance and will fail with “Object initialized twice” if attempted.

How do I open a second instance of Excel?

1. Press and hold Alt.

2. Right-click the Excel icon in the Windows taskbar.

3. Click the Excel icon above Pin/Unpin.

4. Continue holding Alt until prompted “Do you want to start a new instance of Excel?” Click Yes and release Alt.

Why did @RISK appear in the second instance anyway?

• Check Task Manager (Ctrl+Shift+Esc) for two Excel processes. If only one appears, you released Alt too soon.

• If two Excel processes exist and @RISK still opened, your settings may have it configured to launch automatically with Excel.

How to prevent DTS from opening in the second instance:

1. Close one Excel copy.

2. In the remaining Excel instance, go to File → Options → Add-Ins.

3. At the bottom, next to Manage: Excel Add-Ins, click Go.

4. Uncheck all DecisionTools Suite add-ins.

Important: You cannot have two Excel instances both running DTS software, even if they are different DTS applications.