Salut,
I posted this on your earlier thread but it was deleted, so I will add it here as well:
First, I hope you are installing the most recent version of AtoM!
ICA-AtoM 1.x is no longer being maintained or developed. We released AtoM 2.0 in 2013, and have been building on this since - the most recent release is
AtoM 2.7.1. This is the same base code as ICA-AtoM 1.x, developed and maintained by the same team and released under the same license. However, in addition to updating the branding, we have added many new features, performance enhancements, bug fixes, and security patches since, including a new theme, a new faster search index, and more. All the documentation has been rewritten as well - please visit:
If you are attempting to install an older ICA-AtoM release, please consider AtoM 2.x instead!
In the meantime: it sounds to me like an error in your webserver configuration. If you search your error online, you will find that this has to do with how you have attempted to configure Apache as your webserver, specifically in the .htaccess file. See for example:
That is the most advice I can offer at this time, because in AtoM 2.x we now recommend using Nginx as the webserver instead of Apache.
If you are able, please try installing AtoM 2.7.1 instead! See: