After installing IQ feed 4.2.1.4, you will receive a java applet error, "This application has unexpectedly quit".
Close out Market Aspects completely, you may need to reboot to ensure nothing else is running. Close all other programs.
Go to Control Panel, then Add/Remove Programs. Find IQ feed 2.3.0.1 (may not list a version nmber, just IQ Feed, not 4.2.1.4) and remove.
Reboot your computer.
Go to http://marketaspects.tradesignals.com/tpl/download to re-install Market Aspects, you may want to save your workspaces to the desktop first.
When you re-install, say no both times it the installer asks you to reboot.
Once the install is complete, go to My Computer. Go to C:\Program Files\MarketAspects. Locate the files IQ32.dll, IQconnect.exe, and IQ Link Launcher.exe. Right click and delete. Reboot your computer.
Open Market Aspects- this should bring up the IQ Connect Window. If it does not, in the Market Aspects window, go to Configure, then Data Feed- type in your IQ login and password here, then close and re-open Market Aspects.
The IQ connect window should show version 4.2. You should be able to login and receive data.
If not, go to My Computer, and remove all other IQ files with version 2.3.0.1. Reboot, then retry Market Aspects.
For additional troubleshooting help, we may want to try this over the phone. We do have a Market Aspects/IQ customer working and receiving quotes with 4.2.1.4.

Attatched is what your C:\Program Files\Market Aspects folder should look like after re-installing and removing IQ 2.3.0.1 files.