Install any extension and site crashes and goes into maintenance mode. please help

[kireol]

I tried asking in the extensions forum, but never heard a response.

When I try to install any extension, my site goes offline (maintenance mode).

I'm installing them through the magento connect manager.

An example extension would be http://connect20.magentocommerce.com/community/TBT_Enhancedgrid

I have some extensions previously installed.

I'm running  Magento CE ver. 1.9.0.1 on an ubuntu LAMP machine.

I've tried removing any unused modules and clearing var -> cache

What should I do?

[chiefair]

Installing modules requires that you take the site down for maintenance, disable the compiler, clear and disable Magento caching before installing the module.

If you drive a module install home like driving a spike with a sledgehammer, you can split/break whatever you're driving it into, in this case, your ecommerce website. The following prep steps found in the link are akin to boring a pilot hole so it's less likely to split/break things as the spike drives home.

Magento Installation Steps covers this pretty well.

As to Magento Connect not cleaning up after install and getting a 503 error, that's pretty standard with Magento Connect installs. Find the file maintenance.flag in your Magento root directory and delete it.

The maintenance.flag file puts Magento into maintenance mode and stops access to the site during module installation so the installer scripts that run after module installation can have half a chance to run properly on a busy website.

[kireol]

I figured I'd post the solution here since it has not been posted yet.

There's a bug in the CE in that it doesnt use the correct method.  There should be a check for the OS, and then use the correct method.

edit this file:

downloader/lib/Mage/Archive/Helper/File/Gz.php

Change

$this->_fileHandler = @gzopen($this->_filePath, $mode);

to

$this->_fileHandler = @gzopen64($this->_filePath, $mode);

[queeneth]

i have the same problem, i cant access my cpanel too. please what do i do?

[JLHC]

You will need to get ahold of the person who has access to your cPanel and have them remove the maintenance.flag file in your Magento's root directory. 

[ManoharGodase]

Thanks