Someone as a joke has set a picture to appear during my startup screen and I don't know how to remove it and regain my old startup screen. If you know how to do this please help. Thanks.

To make a startup sceen that would allow you to have a picture of your choice appear instead of the "Welcome to Macintosh" or the newer "MAC OS" pictures, during the startup process, is really very simple. Basically, get a picture file you like, save the file as a file type of startupscreen or PICT resource, either one is fine, and also rename it to "startupscreen" & place it inside the system folder (making sure not to accidentally place it inside of any sub-folders within the system folder). Step-By-Step Instructions: First, make or get a cool picture that you'll want to see every time you startup your Macintosh (of course, you can always remove it or put in another one, so don't worry) Now, open the picture with a graphics program. Next, with the picture open, pull down the file menu, use the "save as" command. In this save as dialog box, you should have the option to select a "filetype" or "output file format". Pull down this menu & select "startupscreen" if its available. Rename the file to "startupscreen" (no spaces in between the words), navigate to have it save your file inside of your system folder, and hit the "save" button. GIF Converter, and some other color graphics application programs, such as Canvas, SuperPaint, and Color MacCheese, have a startup screen option: they let you save a document specifically as a startup screen. If "saving as" file type of startupscreen is not an option, choose file type of "PICT resource", (like in JPEGView, for example). As far as getting the ORIGIONAL image back, I don't know.

All you have to do to get the original image back is remove the file "Startupscreen" from the system folder, and the screen will return to its default, factory-set image upon the next startup.

You might need to use ResEdit to change the startup screen. Make a copy of the System suitcase in you System Folder. Open it in ResEdit. In the opened window, you will see a resource called 'Pict', open it. One of the graphics in there will be your startup screen. After double-clicking the startup graphic, feel free to paste any new picture onto it. Make sure that the new graphic is the right dimension however. As to getting your old picture back, your kind of sol. But really, now that you know how to change it, do you really want to go back?