The following looks like a long story (it is only 600 words). I do not know what the user's overall knowledge is, and what exactly was already done. Thus the info goes through the motions of configuring and checking most of the common aspects of Windows OS' LAN features.
All aspects should be checked, stating that it "worked before" , or persevering on"I did Not do any thing ", is not a way to deal with current Sharing problems.
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Win7 when configured on peer-to-peer Network has three types of Sharing configurations.
HomeGroup = Works only between Win 7 computers. This type of configuration makes it very easy to Entry Level Users to start Network sharing.
Home Network or Work Network = Basically similar(and better) to the previous methods of Work Group sharing that let you control what, how, and to whom folders would be shared with.
Public Sharing = Public Network (like Internet cafe) to reduce security risks.
For best results log to each computer's System Screen and set all the computers to be on a with the same Work Group name while each computer has its own unique name.
http://www.ezlan.net/Win7/net_name.jpg
Make sure that the Software Firewall, AV, or other components of Security allow free local traffic on all Networked computers. If you use 3rd party Security On, Vista/XP Native Firewall should be Off, and the active Firewall has to adjusted to your Network IP numbers on what is some time called the Trusted Zone (consult your 3rd Party Firewall instructions
General example,
http://www.ezlan.net/faq.html#trusted
Please Note that some 3rd party Software Firewalls/AV/Security suits keep blocking aspects of Local Traffic even it they are turned Off (disabled). If possible configure the Firewall correctly, or totally uninstall it to allow clean flow of local network traffic.
If end up with the 3rd party software uninstalled or disabled, make sure that Windows native Firewall is On .
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If your network is comprised of Win 7 only and you want a simple Network, use this.
http://windows.microsoft.com/en-us/windows7/help/videos/sharing-files-with-homegroup
After configuring the Homegroup scroll down to the Permission/Security section.
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Networking Win 7 with other version of Windows as Work Network (works very well if all computers are Win 7 too).
In the Network Center, clicking on the Network type opens the window to the right.
Choose your type of Network. Notice the check mark at the bottom, and check/uncheck it according to your needs.
http://www.ezlan.net/Win7/net_type.jpg
Win 7 -
http://windows.microsoft.com/en-us/...mputers-running-different-versions-of-Windows
Win 7 Work Network specific folder sharing -
http://www.onecomputerguy.com/windows7/windows7_sharing.htm
When finished with the setting of the system it is advisable to Reboot all the hardware including the Router and all computers involved.
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If you have Permission and Security issues with Vista/Win7, check the following settings.
Point to the a Folder that meant to to be share. Right click and choose properties.
In the properties
Click on the Security tab shown in the pic bellow to the right) and check that the users and their permission (shown in the pic bellow center and left) are correctly configured. Then do the same to the Permission tab.
http://www.ezlan.net/Win7/Permission-Security.jpg
In both the Security panel, and the Permission panel you have to highlight each User/Group and examine that the Permission Controls are checked correctly.
When everything is OK, Reboot the Network (Router, and computer).
* Note . The Groups and Users shown in the screen-shoot are just an example. Your list will look the way your system is configured.
**Note . All users that are allowed to share need to have account onall the computers that they are allowed to connect to.
Everyone is an account, it means a group of all of the users that already have an account and been established as users. It is available to avoid the need of configuring permission to each on its own, it does not mean
Everyone that feel that they would like to login.
When done hard reboot all Network's computers and the Router.