If you have the product installed and you're going to install an update which has the same version, please just install it over existing version and it will preserve all the settings.

If you have an earlier version installed and you're going to install any newer, you may want to follow on of the ways shown below:

1. uninstall previous, then install new one.
In this case you will definitely lose all the settings and in particular settings for accounts. So back them up if you care.

2. install into different directory.
In this case you'll get two versions installed simultaneously. If debugger major/minor version is the same, they will be able to debug files. If versions do not match, the latest version will work with debugger while the previous will not. You will need to run phped\debugger\register.bat file located in the server subdirectory of the product|version you want to switch to.

3. install over previous version.
In this case all the settings will be preserved, except the one shown below:
-Layout will be dropped to the default (it's done intentionally or you won't see changes in menus and toolbars)

If you're going to transfer PhpED onto another machine, please check this thread: new-computer-way-to-keep-all-settings-t4350.html