SPSS custom dialogs are extensions of SPSS’ point-click menu, officially known as the GUI (“graphical user interface”).

SPSS Custom Dialogs in Menu

Custom dialogs are kept in files with the .spd file extension. After installing a custom dialog file, it will appear in the menu just like an SPSS' built-in command. The difference, however, is that SPSS users can build and share custom dialogs themselves, which isn't as difficult as it may seem.
SPSS Tutorials offers freely downloadable custom dialogs under Tools. Custom dialogs were introduced to SPSS in version 17.

Installing SPSS Custom Dialogs

Option 1: the easiest way to install a custom dialog is simply double clicking the .spd file. A dialog window will pop up and ask you whether you'd like to install or edit the custom dialog. SPSS Custom Dialog Installation

Option 2: If you have more than one SPSS version installed on your computer, right-click the .spd file and select the version in which you'd like to install it. Again, the installation window will pop up after doing so. SPSS Custom Dialogs in Menu

Option 3: alternatively, select Utilities Custom Dialogs Install Custom Dialog. SPSS Custom Dialogs in Menu Navigate to the .spd file. Clicking Open will launch the installer window.

In some cases, SPSS may throw an Chi-Square Goodness-of-Fit Test - Simple Tutorial when you first install a custom dialog. Don't let this put you off. Troubleshooting this common error is not hard and needs to be done only once; subsequent custom dialogs will install more smoothly.

Uninstalling SPSS Custom Dialogs

Unfortunately, uninstalling SPSS custom dialogs is not straightforward and we strongly dislike the way this has been implemented in SPSS.

Option 1: open an .spd file as if you'd like to install it. This doesn't have to be the custom dialog you'd like to uninstall; any .spd file will do. Now, select Edit as if you'd like to modify the custom dialog.

This will open an SPSS custom dialog builder window. You're probably not familiar with this window but don't panic, everything will be OK. Navigate to File Uninstall as shown below.

SPSS Custom Dialog Builder Window

You now get a list of all custom dialogs installed (which is unrelated to the particular .spd file you used in order to arrive here). Select any custom dialog you'd like to uninstall. Clicking Ok will uninstall it after asking whether you'd like to save the contents to a new .spd file. Close the custom dialog builder window without saving it when you're done.

Option 2: (re)install any custom dialog. After doing so successfully, a window pops up that tells you where it was installed. Navigate to this folder and delete it entirely. Note: by default, some of these folders may be hidden in MS Windows.

SPSS Custom Dialogs - What are They?

Technically, a custom dialogs (.spd) files are archive files: zipped folders holding several smaller files. If you're curious, unzip one with 7 Zip to see what's inside.
A custom dialog's main element is the dialog window as the end user will see it. It may contain various elements such as plain text, variable selectors, text input and tick boxes. SPSS Custom Dialog Window

SPSS Custom Dialogs - How do they Work?

Underlying a custom dialog is syntax written by the author. It may contain placeholders that are replaced by whatever the end user specifies in the dialog window elements. This syntax, with the placeholders filled in, is run or pasted when Ok or Paste is clicked.

Note that many custom dialogs require the SPSS Python Essentials to be properly installed. If so, this should be clearly indicated on the dialog window itself and preferably in its user instructions as well.
Optionally, a Custom Dialog may contain a help file in HTML. If this is omitted, Help will be greyed out in the dialog window. Clicking Help in one of our Tools will point your (default) web browser to the tutorial in which it was presented.