Download Docman
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Visit http://www.joomlatools.eu/docman-14.html and download Docman v1.4.0. There is a more modern version of Docman that is commercial. We're using the free version in this tutorial.
Enable the Legacy Plugin
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Login to the administrator area of your Joomla site and go to Extensions >> Plugin Manager. Click to enable the "System - Legacy" plugin.
Install Docman
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Go to Extensions >> Install/Uninstall and click "Browse" to upload Docman
Add a New Category
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Go to Components >> Docman >> Categories and click "New" in the top-right corner.
Name and Save the Category
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Give your new category a name and click "Save" in the top-right corner.
Start Uploading Documents
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Click "Files" and then "Upload" in the top-right corner.
Choose Upload Option
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Normally you'll want to keep this option as it is and just click "Next>>>"
Upload Your File
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Browse to find your file and then click "Submit"
Choose to Make a New Document
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Once you have uploaded your file, the next step is to create a "Document" out of it. That simply means giving it a name, description and other details. Click "Make a new document entry using this file."
Add Details to the Document
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Make sure that both "Approved" and "Published" are set to "Yes". Then click "Save".
Verify that Your Document is Created
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Hopefully your new document will appear as above.
Make a Menu Link to Docman
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Go to Menus >> Main Menu >> click on "New" >> choose "Docman". Choose a title for your menu link and click "Save".
View Docman On the Front of Your Site
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Click "Preview" in the top-right corner and you'll see your new menu link. Click on it and you'll see your Docman category. Open the category to see your file
Extra Feature: Docman Groups
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Docman also has a very powerful permissions system that allows you to control who can and cannot access documents. Start by going to Components >> Docman >> Groups
Creating a Docman Group
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Click "Add" in the top-right corner". You can create a group of users simply by moving them from the "users available" list to the "Members in this Group" list.
Giving Groups Access to a Document
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Now when you open up any document you can click "Permissions" and give access only to a certain group of users.