update error! and two more issues

[dee_viz]

Hello all,
I have three queries.

I was trying to install a console application in my E61i. I was using some simple hello world program, signed it with devcert and installed it with UIDs assigned by carbide itself [ my ignorance, pardon me ]. Since I have a developer certificate, I changed the UID and tried to install it again. It is giving me update error. I know its because i have changed the EXE's UID.

How can i reinstall the application? I removed the previous application and tried installation. While installing, it asks, the application exists and do you want to replace it. After removing it, how can it exist again?

How can I 'fake' it? i mean, install the same app, but make some changes so that the OS identifies it as a new EXE? Where should I change the application?

My second query.
Earlier[with the previous UID] when i tried installing it, it got installed successfully. I was using the wrong UIDs, I know. It was not showing up in the 'Installed items'. Is it because I used the wrong UID?

3rd
Can we build a program which runs in the background using symbian C++? a Daemon? If yes, How can I make it run the background?

any kind of help will be much appreciated.

Thanks
Deepak.

[wizard_hu_]

How can i reinstall the application? I removed the previous application and tried installation. While installing, it asks, the application exists and do you want to replace it. After removing it, how can it exist again?

The installer identifies installed components by their package-UID (the one you specify in the .pkg file). Can it happen that you have re-used the .pkg file from another project?

How can I 'fake' it? i mean, install the same app, but make some changes so that the OS identifies it as a new EXE? Where should I change the application?

You should change the UID:
- in the .mmp file
- in ...Application::AppDllUid
- in the _reg.rss file
- in the .pkg file
You also need to change the name of the executable. You can rename all the files in installation-time ("...\old.exe"-"!:\sis\bin\new.exe", and the same for the .rsc files), but it should be pre-modified in the _reg.rss file.

Can we build a program which runs in the background using symbian C++? a Daemon? If yes, How can I make it run the background?

Yes, you can search for autostart in this forum, or in the wiki. You can also check Startup List Management API in the SDK Help. Note that you will need a protected UID, thus you will also need a devcert for testing automatic startup.

[dee_viz]

Thanks wizard_hu_

I am gonna try the autostart option, [i think ihave seen posts here earlier on that] n check out the API also.