Thanks for hanging in there.
I am wondering if your removal of X3 was complete or not, as there are a few things to be done in addition to going into Control Panel>Uninstall a Program.
So, if you don't mind one more crack at removing X3 and installing it again, please do the following:
1. Go into Control Panel>Uninstall a Program, and run the uninstaller for Sonar X3 (both 32-bit and 64-bit, if installed). If it asks you if you want to delete any unused items, tell it 'No To All'.
2. Now, open a Windows Explorer window and paste the following into the address bar, without any quotes, and hit Enter:
'C:\Users\your-user-name-goes-here\AppData\Roaming\Cakewalk'
3. OK, for the above, if you see a sub-folder called SONAR X3 Producer, delete it.
4. Now paste the following path into the address bar of the Windows Explorer window, again without the quotes, and then hit Enter:
'C:\Program Files\Cakewalk'
5. For the above, which is for a 64-bit X3 install, look for a sub-folder called 'SONAR X3 Producer', and if there delete it.
6. Now paste the following path into the address bar of the Windows Explorer window, again without the quotes, and then hit Enter:
'C:\Program Files (x86)\Cakewalk'
7. For the above, which is for a 32-bit X3 install, look for a sub-folder called 'SONAR X3 Producer', and if there delete it.
8. Now it's time to delete 2 registry keys, if present. Run Regedit (the Windows Registry Editor). There are 2 keys to look for, one for 32-bit X3 and the other for 64-bit X3:
\HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Cakewalk Music Software\SONAR Producer\
The above is for 32-bit X3. Once this key is opened, look for a SUB-key called X3, and if that sub-key is there, then delete it. (meaning delete the X3 sub-key, if present).
\HKEY_LOCAL_MACHINE\SOFTWARE\Cakewalk Music Software\SONAR Producer\
The above is for a 64-bit X3 install. Again, after opening the above key, look for a SUB-key of X3, and delete the X3 sub-key, if present.
The above steps should get completely rid of a 32-bit and a 64-bit X3 install, and once these steps are completed, you should be able to do a clean install of X3, making SURE this time around to right-click on the installer and then click on 'Run As Administrator'.
Sorry to put you through that again, but if there were any remnants of X3 they could have theoretically jazzed things up.
Please perform the above steps and post back after completing the install and seeing if that took care of it.
Bob Bone