How would I rename the component with the same old name in SKM. When I try to rename the component with the same old name, it gives me a message "Non-unique name in this or other scenarios". Please note that I did no destroyed the component I have only removed it from Single line diagram before renaming.

You cannot name a component by the same name. If you created a new drawing in skm and want the existing name to populate so you can add more loads...etc.

Goto "component", "existing" select your device and skm will populate and still have it connected to the electrical system

If you have a legitimate SKM package with a current maintenance agreement, you should get comfortable with their support group. They are excellent to work with, and you've paid for the service. support@skm.com or 800 232-6789.

I have a legal SKM package but the package does not include support.

You should look at the differences between remove and destroy. AS JCV says, all component names must be unique. Your component that has been "removed" still exists in your one line. It's just been collapsed out of view.

While their "maintenance" agreements are over priced (WAY over priced) their support can be quite helpful. If you just purchased the software it usually comes with 1 year of support. It also gets you the bug fixes and upgrades

That being said, I don't think you understand what is going on, or the difference in SKM between "remove" and "destroy"

To get the message you did, means that you are NOT taking a component named "X" and renaming it "X". TO get that message you are either trying to create a new component, and calling it "X", while "X" still exists, or are trying to rename another component ("Y") to "X" while "X" still exisits.

All components have to have completley unique names, and do not have to be on ANY single line to still exist.
Esentially PTW is a database program, and a single line is just ONE method of displaying some of the data in it. If you remove a component from a single line, it does NOT remove the component from the data base. Nor does it remove the connections the component had.

Open up a "component editor" window, and scroll down to your component name, and you will see that it is still listed. [Note that you have to scroll through each type separately]
To place that component back on a single line, right click on your single line, and then click on "existing", then again scroll down through the component types, down to your component.