You certainly have noticed the new Scene Explorer that replaced the old “Select Objects” dialog box since version 2008. Although very innovative it behaves painfully slow sometimes. Particularly when you import or link large architectural projects with thousands of objects from Revit or AutoCAD.

You can try either one of two tricks:

1) Remove all the columns you will not likely use from the dialog. If all you have in there is the name, it should be considerably faster.

2) Put the old “Select Objects” dialog back by editing the ini file:

Close 3ds Max
Open the CurrentDefaults.ini in any text editor and change this line:
[Scene Explorer]

Save and reopen Max

1 launches the new Scene Explorer
0 launches the “good ol’ reliable”

You actually have to find the CurrentDefaults.ini of your current UI switch.
As of V-Ray 1.50 SP2 this is now available from the Custom UI and Defaults Switcher in 3ds Max ( So if you are using the Max.vray tool option You will find the ini here: C:Documents and Settings<username>Local SettingsApplication DataAutodesk3dsmax2009 – 32bitenudefaultsMAX.vray

These are some other possible locations:

Windows XP 64 bit build:
C:Documents and Settings<username>Local SettingsApplication DataAutodesk3dsmax2008 – 64bitenudefaultsMAX

Windows Vista 32 bit build:
C:Users<username>AppDataLocalAutodesk3dsmax 2008 – 32bitenudefaultsMAX

Windows Vista 64 bit build:
C:Users<username>AppDataLocalAutodesk3dsmax 2008 – 64bitenudefaultsMAX