Could not write to the configuration file

[C4rnage]

I am using IIS on Windows 7 and completely new to Joomla installation and administration.
I had previously changed the permissions of my "wwwroot/joomla" folder to read\write for "LocalPC/IIS_IUSRS" and was having problems upgrading from 2.5.6 to 2.5.7 so I did the manual overwrite option as suggested by "humvee" in an alternate post. After the overwrite, I was then unable to install a template. I checked\double-checked the permissions on the folder(s) as my understanding of IIS is that it runs under it's own user as mentioned LocalPC/IIS_IUSRS.
I saw another post suggesting that the folder\file ownership needs to also be this user, but this had no effect.

I then spotted the permissions tab:
Admin > Site (top left) > System Information > Directory Permissions (tab) >
and noticed everything except my "tmp" folder was "unwriteable" from Joomla's perspective. I couldn't understand this and the only difference in permissions between the "tmp" folder and everything else under "wwwroot/joomla" was that the Windows logged in user, Me, did not have write permissions on the other folders\files.
I changed this, did an iisreset, the permissions tab now showed all as "writeable" and I can now make changes to configuration.php and attempted to install my first template from the Packages install.
I am now past the packages install permissions error, but now I get the following:
JInstaller: :Install: Cannot find Joomla XML setup file
JInstaller: :Install: Cannot find XML setup file

I will continue working my way through this, but could somebody explain why I need to allow permissions on the Joomla folders, rather than the IIS user please, as it goes against my understanding. I have read various topical posts on permissions and the official Joomla docs and cannot find an explanation
Thanks in advance

[humvee]

Hi
Welcome to Joomla and to these forums.
I have split this topic into a separate thread. It is not advisable to hijack someone else's thread as this makes it all the more difficult to help both parties, particularly as in your case you are on a completely different server set up than the original thread user! Please see forum rules for details on how to post to these forums.

Please run the Forum Post Assistant to provide the information to help us try and resolve the issue.
Please follow the instructions in the post and the program pack closely



[Mod note: Moved from Installation Forum to IIS Forum; ]
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