There are a few terms that may be causing confusion that are quite often conflated of which I admittedly do myself that I'd like to cover that might help add clarification to the conversation (if I am oversimplifying by stating the obvious and you are
aware of the differences below, regarding terms
referencing the PP "process" versus the PP "GUI" in regards to the terms "Start" and "Open", then please
scroll on down to the bottom of the post where you will find steps to check to see if your ini file might be set to "Read-only" and forgive me for all the excess verbiage

).
Terms "Start"/"Exit" - Starting the POP Peeper program: As far as "starting" POP Peeper this is when the POP Peeper process (program) starts which is done when you boot your system (if the option: "Run POP Peeper at Windows startup" is enabled [checked]). Now if you have "Exited" POP Peeper by right-clicking on the POP Peeper icon in the system-tray and selected "Exit"

- Exit PP.png (9.34 KiB) Viewed 6135 times
you have then stopped the POP Peeper process (program)in which case you would then need to start the POP Peeper process (program) again using the Windows start Program list or if you have a desktop POP Peeper icon clicking on that icon (which in this case if the POP Peeper process is stopped results in the same thing that occurs when booting the computer). All this time while the POP Peeper process (program) is running POP Peeper will check for incoming messages. On the other hand, to "open" the POP Peeper GUI to interface with the program while the POP Peeper process is running the interface has to be "opened" as explained below.
Terms "Open"/"Close" - Opening the POP Peeper interface (GUI): In regards to when you "open" POP Peeper, this is when you either double-click on the system tray icon (assuming "single-click" option is not used) or right-click the system tray icon and select "Open POP Peeper" or you click on a POP peeper desktop icon to "open" the POP Peeper interface window, while the POP Peeper process (program) is running. (Keeping in mind, the POP Peeper program is of course still running in this case whether you have the POP Peeper interface "open" or not). Of course by clicking on the red "X" in the upper-right corner of the POP Peeper interface you then "close" the POP Peeper interface but again the POP Peeper process (program) remains running (which is evidenced by the fact you will get message alerts when messages arrive) and the POP Peeper process is ONLY stopped by "Exiting" POP Peeper as mentioned above. All of this may not be fully understood by some who are not very familiar with computers in general that much.
In any case, in regards to POP Peeper sustaining its window size, you might want to check to see if your poppeeper ini file happens to be set to the "Read-only" (right-protected) state.
But before we check this I have a question (in reference to my explanations above specifically regarding "terms") in order to help clarify what the specific problem is that you are reporting. If your only problem is when you "close" the POP Peeper interface and then "open" POP Peeper again the window size is the same but is not what you want (not maximized) then all you should need to do is maximize the POP Peeper interface before you "close" POP Peeper and that size should be maintained. More specifically, If you are saying when you click on the POP Peeper icon to "open" PP that POP Peeper "opens" the interface window small (not maximized) as illustrated in the screen-shot below?

If this is what is happening, if you hover over the "maximize" (blue box button in this screen-shot) button you will get a tool-tip message that says "maximize" as illustrated. If you click on that to maximize the PP interface window and then "close" POP Peeper (click on red "x" in upper right corner) and then "open" POP Peeper again by clicking on the POP Peeper icon as before, does POP Peeper "open" maximized this time or smaller again as illustrated in the screen-shot? Now if you "exit" POP Peeper (that is right-click on the POP Peeper icon in the system try and select "Exit") then "start" POP Peeper again, does POP Peeper "open" maximized this time or does it "open" once again as before in a smaller screen? On the other hand, if this has been your problem and POP Peeper now "opens" maximized as it had been when you "exited" it before then perhaps your problem is solved as it was just a matter of leaving the GUI in the desired size when doing a GUI "close". You might want to reboot your computer to see if you are now getting what you want as far as when you "open" POP Peeper (assuming this is your problem). On the other hand, if the problem is when POP Peeper "starts" up (at computer boot up or when you "start" POP Peeper again after "exiting"), i.e. POP Peeper does not "start" minimized but instead the interface "opens" when you "start" POP Peeper then this is an entirely different situation the cause of which I'm not at all certain based on what we know from previous posts (perhaps what is outlined below might help if applicable).
Check to see if your ini file might be set to "Read-only":
1) Using Windows Explorer go to where your ini file is located (based on the path in your screen-shot)
2) There will be an ini file named poppeeper as illustrated in the screen-shot --
right-click on that file and select "Properties"

- Click on image to enlarge for better viewing
3) On the bottom of the 'General' tab, make sure that "read-only" is not enabled -- that is uncheck this "Read-only" option if it is checked (also, if there's an "unblock" button, press it)
4) Oh and be sure to click the "OK" button to save any change.
