The Thunderbird window needs to be maximized for this to work. This "nonsense" is a standard Windows operations and is easy for most computer users.

Makara states in another thread... Thx for the advice ... maximised T/bird window but there is no l.h. panel when I open a new page (Write). It is there on the regular window but I want it back on the Write page.

In the thread you decided to hijack you finally gave some info about your real problem. The 3 month old, solved thread was about the Folder pane on the main page and has nothing to do with your apparent issue. The side panel in a Write window is the Contact Sidebar. You must be in the Write window and use the toolbars in the Write window. Just like turning the light switch on in the garage does nothing for the bathroom lights.

Open a Write window. Do you have a Menu Bar with File-Edit-View etc? If not press the alt key. From the menu bar select View-Contact Sidebar. There is a shortcut to toggle the Contact Sidebar on and off and it is the F9 key.

This is why the forum rules state to start your own thread with details about your issue. As you can see none of the help in the 3 month old thread applied to you.

Again from the other thread Ok I'll hope to avoid you in the future ... some of us are not that tech savvy and sometimes need directions which are without such imperative statements as yours above. Plse, no more on this...I'll plod on as best I can.'

Gee i wish I had seen this before wasting time with additional help. Everyone here are Thunderbird users just like you that volunteer their time to answer questions. There are enough new threads from people that follow the forum rules and open their own thread with details about their problem without people digging up old, solved threads that do not even apply to their problem. I will gladly add you to my ignore list for any of your future questions per your request.