Remote Desktop Web Connection ActiveX control is not installed. A connection cannot be made without a working installed version of the control.
This error is typically encountered after Windows XP SP3 or Windows Small Business Server 2003 SP1 has been installed.
Microsoft RDP ActiveX Control has been disabled by the installation of Windows XP Service Pack 3 or Windows Small Business Server 2003 SP1 on your machine. (why Microsoft, why?)
If the user tries to enable the ActiveX control using the Manage add-ons dialog in Internet Explorer, the Microsoft RDP Active control may not be listed.
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Solution 1:
1. Click Start, Run. Type Regedit.exe and press ENTER
2. Navigate to the following branch:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Ext\Settings
3. Double-click Settings to expand the branch.
4. Right-click {7584c670-2274-4efb-b00b-d6aaba6d3850} and choose Delete
(Repeat step 4 to delete any other problem keys)
5. Click Yes when asked for confirmation.
Close all instances of Internet Explorer and re-run Remote Desktop Web Connection.
Sloution 2:
Enable the below class ID:
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Ext\Settings\{7584c670-2274-4efb-b00b-d6aaba6d3850}]
Disable the below class ID:
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Ext\Settings\{7584c670-2274-4efb-b00b-d6aaba6d3850}]
"Flags"=dword:00000001
"Version"="*"
Example of all the registry keys that you may need to delete to make it all work:
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Ext\Settings\{7584c670-2274-4efb-b00b-d6aaba6d3850}]
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Ext\Settings\{4eb89ff4-7f78-4a0f-8b8d-2bf02e94e4b2}]
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Ext\Settings\{7390f3d8-0439-4c05-91e3-cf5cb290c3d0}]