Q: During installation of com_joomlastats_vx.y.x.zip I have one of below errors.
"there is a error during uploading the file on to the server"
"no installationpackage found"
"Fatal error: Maximum execution time of 30 seconds exceeded (...)"
How can I install main component?
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A: Follow below steps:
1. Unzipp the package "com_joomlastats_v3.0.0.zip" into a directory, e.g. "c:\temp\joomstats"
2. On your webserver create a new directory in the Joomla-Temp-Directory ("(...)/joomla/tmp"), e.g."inst_v3". You should have "(...)/joomla/tmp/inst_v3/" directory
3. copy all files of "c:\temp\joomstats" via FTP into the Joomla-Temp-Directory, in my case it was "(...)/joomla/tmp/inst_v3/" 
4. go to the joomla back end, then menu "Extensions" - "Install/Uninstall" - "Install from Directory". Type in the temp path where you have copied the files ("(...)/joomla/tmp/inst_v3/" an press the button "install".
5. Now You can delete files from "(...)/joomla/tmp/inst_v3/" directory
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Explanation:
JoomlaStats component is sophisticated program. It contain many files that need to be unzipped and copied to right places. Additionally during installation JoomlaStats database is being updated which takes time and resources. If You have week server or Your server is overloaded, installation could fail due to performace reasons.
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Thanks for rdeutsch, who prepare this FAQ.