Can I do this simple site with Drupal?
The site will be very simple, it will help the work flow of a research group.
It will be able to:
- Create groups of members, permissions and accesses.
- The members of the group will be able to exchange files with all the group or just a member, files like text files, pdf's or images. And when they exchange data, the site must save who have exchange and what have been sent.
- Create an administration group that can manage everything, like creating groups, deleting them, create a member, see what members have been exchanging, and stuff like that.
- The groups can´t access to data of the other groups.
- It will have an agenda or a calendar with the tasks and deadlines of the each group.
- Show the final works to the public.
So, can I do this with Drupal?
And please, can you tell me what Modules will I need?
Thank you!

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organic groups.module and the core modules permissions system.
Also..
.. the OG calander module
thanks! And for exchanging
thanks!
And for exchanging files members/members or member/group, in other words, one member upload a file and that file can be downloaded by a member or all the group (the member decides that), do I need some ftp module? Or with the basics can I do that?
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there are file management and user access modules available in the downloads area.
"organic groups.module and
"organic groups.module and the core modules permissions system."
This i couldn't find :S can you send me the links to that modules please?
The OG Calendar i've found
oops
cancel the OG Calander module as it no longer supported. the OG module can be found here http://drupal.org/project/og
core modules come with the default drupal installation.
calendar
Oh, but if OG Calendar is no longer supported, how can I implement a calendar to define to each group their deadlines and events?
There is another module? Or, i can not implement that at all?
Not really..
..sure how to do it, maybe use the standard calander module and use views with arguments. Only a suggestion, maybe someone else can help.
Good luck!
just one more question
Because OG Calendar is a project no longer being maintained, it should not be used, or it can't be use at all?
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If it is still published it can still be used. Just becaus it is no longer being maintained does not mean it doesn't work. If there was a security issue with it. The module would be unpublished. However any bugs found (if any) would have to be handled by you, a developer or the community using the module by way of the issue queue for the project in question.