1, the first thought is that the system has program residues, which may not be completely deleted, so it cannot be installed. So use re browser to search the relevant keywords of the program, delete all the found relevant files and directories, and then restart the installation program, the result is invalid;
2. I thought I had a backup before, so I opened the titanium backup, found the relevant software, and resumed: at first, I chose the program+data, indicating that the recovery failed, and later I chose the recovery program alone, indicating that the recovery was successful, but I didn't see a successful program in the system, so I was fooled (I didn't try to restart the system here, and I don't know whether it is effective to restart the system after recovery, so interested friends can try it ~);
There is no choice but Google. The most successful method is to connect the computer or find it in storage mode. Android_secure folder under SD card directory with Root Explorer. There should be a smdl2tmp 1.asec in it, and there may be other names. In short, I deleted the file whose naming format is obviously different from the normal program and tried to reinstall the software, but I couldn't find the relevant directory in the system and SD card.
4. The second method: If the installation of the application prompt on the PC fails, please check whether the USB driver corresponding to the Android phone is installed first. Generally, using 9 1 mobile assistant or pea clip will automatically help you install the mobile phone driver. My mobile phone prompt failed, my driver was installed correctly, and pea pods used it normally, so this has nothing to do with me;
5. The third method: check whether the mobile phone settings-applications-unknown sources have been checked, otherwise some applications not provided by the electronic market will not be installed, I have checked, so this has nothing to do with me;
6. The fourth method: use the program management provided by the system to view the programs on the SD card. Some programs don't actually have colored icons. It turns out that these softwares without icons are at work. These software without icons are incomplete software data that have not been installed or uninstalled correctly before. If you install them again, you will report an error. Now we use the software management provided by the system to clean them up, so that there will be no mistakes in reinstalling the software. But I can't even see the icon of program management provided by the system, so this method.
7. The fifth method: directly delete/mnt/secure/asec/smdl2tmp1. Asec (in drive mode: removable disk/. android _ secure/smdl2tmp 1。 Asec) and then install. This method is a supplement to the first method, but unfortunately my system and card also have it.
8. Sixth method: When upgrading the installed program, you will be prompted "The application is not installed". Some software will appear when upgrading. You can only uninstall the old version and install the new version. I can't find the uninstall at all, so it's useless.
9. The seventh method: Check Settings-Development-Allow Simulation Location, and it will be OK. It's still useless for me to tick this;
10, the eighth method: after connecting the mobile phone to the computer, open 9 1 mobile assistant, install an application at will, and select the installation path as the memory of the mobile phone. I am a 2. 1 system, and the original software is installed in the "memory", so this is useless;
1 1, the ninth method: Some software signatures have changed, so it can't be cover the installation. Just delete and reinstall the new version. This principle is the same as the sixth method, so it is invalid for me;
12, the tenth method: restore the factory settings directly, which is a method I don't want to do and should be effective in theory.
After all these attempts, the problem still cannot be solved. It's really depressing. Must I go back to the factory? Hesitate again and again, I have already begun to prepare for reloading. As a result, when I was searching for the installation principle of Android system, I found a solution to this problem that has been bothering me for a long time. Let's look at the solution:
In fact, the program installation of Android system is to copy the APK file to the APP directory and give permission, and the backup is also to copy the APK file and related data files. According to this principle, I did the following:
1. Download the APK installation package of the application first and put it in the SD card;
2. Rename the APK file to the form of com.xxx.xxx.apk (compare the file names in the system APP directory).
3. put it in the app folder, modify the permissions and install it.
4. Still "Program Not Installed"