You can try this if you haven't already found a solution.
1.Press the Windows key Press the Windows key + R to open a Run window.
2.Type regedit and click OK.
3.Press CTRL + F and enter 0006F03A-0000-0000-C000-000000000046 into the search box, then click Find Next.
4.Delete the key by right-clicking on the entry and click Delete.
5.Press F3 to repeat the search until no more registry keys are found.
or
Registry Fix for Signature and Stationary issues in Outlook 2010
Here are the instructions for correcting the issue for a 32 bit version of outlook: Signature problems:
Regedit the following keys: HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Wow6432Node\CLSID\{0006F03A-0000-0000-C000-000000000046}\LocalServer32 and HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{0006F03A-0000-0000-C000-000000000046}\LocalServer32 Change both (Default) and LocalServer32 values in each to C:\Program Files (x86)\Microsoft Office\Office14\Outlook.exe However, I am running 64 bit, so luckily someone else had this problem who also was running 64. The instructions just need to be changed to remove (x86) from the path, like so: Signature problems:
Regedit the following keys: HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Wow6432Node\CLSID\{0006F03A-0000-0000-C000-000000000046}\LocalServer32 and HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{0006F03A-0000-0000-C000-000000000046}\LocalServer32 Change both (Default) and LocalServer32 values in each to C:\Program Files\Microsoft Office\Office14\Outlook.exe