Method 1: Let’s run the Homegroup troubleshooter and check if that helps. Refer the following link to run the troubleshooter.
‘Open the HomeGroup troubleshooter’
http://windows.microsoft.com/en-US/windows7/Open-the-HomeGroup-troubleshooter
Method 2: Change Workgroup settings:
Step 1: Please make sure these machines are in the same workgroup:
a) To change workgroup settings, please refer to the following steps:
b) Click the Start Button, right click on Computer in the right pane and choose Properties.
c) In the Computer name, domain, and workgroup settings section of the System window, clicks Change settings.
d) On the Computer Name tab of the System Properties dialog box, click Change.
e) In the Computer Name/Domain Changes dialog box, type the name of the workgroup being used by the other computers on your network in Workgroup, and then click OK.
If the issue persists, please refer to step 2:
Step 2: Advanced Share Permission
a) In Windows 7, right-click the shared folder and then click Properties.
b) Click the Sharing tab, click Advanced Sharing. Check Share this folder box.
c) Click Permissions button, Click Add.
d) High light the account which you want to share this folder to (Account name which will access the folder), then check the Allow box for Full control.
e) If the account name is not list, please click Add button. Type Everyone and click OK.
f) Click everyone in the user list, and check the Allow box for Full Control in the "Permissions for Everyone" pane and click Apply, click OK.
Method 3: Disable antivirus software installed on the computer and then try access the files and check if the issue persists.
‘Disable antivirus software’
http://windows.microsoft.com/en-US/windows7/Disable-antivirus-software
Warning: Antivirus software can help protect your computer against viruses and other security threats. In most cases, you shouldn't disable your antivirus software. If you have to temporarily disable it to install other software, you should re-enable it as soon as you're done. If you're connected to the Internet or a network while your antivirus software is disabled, your computer is vulnerable to attacks.
