If you got an error "is not a valid Pocket PC application" while installing on PDA:
1. If file has EXE extension, then you should install it from PC via ActiveSync
2. If file has CAB extension, then you install it directly from PDA
3. If file has EXE extension and failed to install from PC, then try to run it from PDA - it is special type of App.
Installing Theme:
1. After you have downloaded the theme, copy it to your device in \Windows or \My documents folder or in root of your memory card.
2. Open Explorer, then \My documents and select your theme.
3. Open Start->Settings->Today. There will be the list of themes in open window. Select your theme and press OK.
Other installation problems:
1. New releases and updates of old applications less support old operation systems (Windows Mobile 2002, 2003, 2003SE) and therefore these application hardly can be installed on these OSes.
2. Most of application are developed for QVGA, but can be run under VGA resolution. In this case there are 4 times more pixels on one dot and the picture is not attractive. So you should install the application with appropriate resolution.
FAQ for Symbian
If you got an error "certificate expired" or "certificate error" while installing Theme, Software or Game:
1. Disable certificates in Tools -> App. Manager, choose Options -> Settings and set Software installation to All and Online certif. check to Off.
2. Try to install Theme, Software or Game. If failed - read next.
3. Go to 'Tools -> Settings -> Date and Time' and change phone date a few years back (at first change 6 months back, then if failed - change 1 year and more back).
4. Try to install Theme, Software or Game.
5. If failed again - change phone date 6 months forward, and then if failed - 1 year forward.
6. Try to install Theme, Software or Game.
7. Change date to current date.
8. If it does not help, then try to sign the file on https://www.symbiansigned.com/app/page/public/openSignedOnline.do
9. Otherwise the application got old and need certification update from the developer. This application harldy can be installed.
Other installation problems:
1. If file has SIS or SISX extension, then, as a rule, it is not supported under different Symbian operation systems, meanwhile such files are usually supported by both 3rd and 5th Edition.
2. If file has JAR or JAD extension, then, as a rule, such JAVA applications are supported by all Symbian versions.
