Only Classic Xref Manager is Available in AutoPLANT

If you're an AutoPLANT user who almost never loads basic AutoCAD then you may have never noticed or even seen the new Xref manager. And if you're a long time AutoPLANT user then you may be saying to yourself (What there is a new Xref manager?). As seen below is an example of the classic and non classic Xref managers:

But why does AutoPLANT only use the classic Xref manager? Well that's because AutoPLANT enforces the Single Document Interface (SDI) by setting the AutoCAD variable SDI to only allow 1 document to open. What is SDI and why does AutoPLANT use it? First SDI disables opening multiple windows in AutoCAD; AutoPLANT writes data to a drawing database and AutoPLANT cannot write to multiple drawing databases simultaneously.

Because SDI is enabled AutoCAD forces the Xref manager to open as the classic window and the new Xref manager cannot be used wile SDI is active. SDI can be togged off and on by entering the command SDI 1 or 0; but AutoPLANT cannot handle multiple documents and write to their databases simultaneously. Do not turn off SDI or there is a risk that drawing database and the project database can become corrupt.

From the System Variable list in the AutoCAD help file SDI has the following entry:

SDI System Variable
Saved in:Registry
Initial value:0

Controls whether the program runs in single- or multiple-document interface.

0      Turns on multiple-drawing interface.
1      Turns off multiple-drawing interface.
2      (Read-only) Multiple-drawing interface is disabled because an application that does not support multiple drawings has been loaded. SDI setting 2 is not saved.
3      (Read-only) Multiple-drawing interface is disabled because the user has set SDI to 1 and an application that does not support multiple drawings has been loaded. (SDI was set to 1 before the application was loaded.) SDI setting 3 is not saved.

If SDI is set to 3, it is reset to 1 when the application that doesn't support multiple drawings is unloaded.

FYI: AutoPLANT, once active set the SDI to 3.