Saving an App with a new name

I saved one of my apps (a multiscreen app) that works perfectly, under a new name. The idea is to build a new app by modifying an old one instead of starting from scratch. The new app, although identical to the first, STOPS as soon as I open the 2nd screen. I tried to solve the problem by removing temporarily the original App from the phone and by naming the version of the new App 1.0; but no success. Any ideas? Thank you.

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usually in this case there are the following 2 recommendations

1. Use different screens wisely

2. Before starting to create another screen, first you should think about is it really necessary? See also Building apps with many screens and SteveJG's post about advantages/disadvantages, because in only one screen you also can use vertical arrangements to simulate different screens, just set the arrangements to visible = true/false as needed... See also Martyn_HK's example about how to use Tabs in AppInventor and another example from Cyd. 

The recommended method of switching screens in App Inventor

manager.aia

3. App Inventor works best if you use images whose size matches the size you want them to appear on your screen. If you import larger images into your app, your app may run out of system memory. Using Images with App Inventor

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to find out more about the Runtime Error, you can use Logcat

I normally use Eclipse and Logcat there, but if you have installed the App Inventor Software (see also http://appinventor.mit.edu/explore/ai2/setup-emulator.html), you already have everything you need to use logcat...

How to use Logcat

1. connect your device using USB with your computer

2. in File Manager go to the App Inventor directory, which is  C:\Program Files\App Inventor or similar

3. press Shift and right mouse click the subdirectory commands-for-Appinventor to get the context menu

4. select "open command window here" and you will get a command window of that subdirectory

5. enter adb logcat and the logcat will start running

6. start your app to elicit the error

7. copy the log (see below)

To copy your log, right click, click "select all" and enter to copy the complete log into the clipboard, then open Notepad and paste it using ctrl-v.

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Thank you for your answer; and for answering rapidly like usual. Youssef.

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