Steps to be followed :
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1. Uninstall Teamviewer
2. Click Start then type ‘%appdata%’ – now delete the Teamviewer folder
3. Click Start the type %temp% and delete the contents of this folder as well as the X:Windowstemp folder
4. Click Start then type ‘regedit’, delete the registry folder found at HKEY_CURRENT_USERSoftwareTeamViewer & the folder HKEY_LOCAL_MACHINESOFTWARETeamViewer
5. Then goto X:Users(Your username)AppDataRoaming > delete the Teamviewer folder [you might have to make hidden folders visible to see it or just type the path into the address bar]
6. Restart your PC
7. Now change your MAC address, either manually or with a tool like TMAC [I suggest changing the MAC address on both network connections, i.e. wireless and LAN]
8. Install TeamViewer [You'll see your PC has a new TeamViewer ID]
Manually changing your MAC Computers Address
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1. Right-click ‘My Computer’ on your desktop and select Manage
2. Go to Device Manager
3. Select Network Adapters
4. Select and double click on the adapter for which you want to change MAC address
5. You will find a properties window with multiple tab. Select Advance tab
6. From Property, find Network Address
7. Now select value and put your 12 digit hexadecimal number
8. Press OK and exit.
Now issue won't come ever.....