What is not explained clearly is the fact that you cannot easily "mix and match" the installations ... if you use the CD for one installation you must do so for them all and the same with the download. But if you want to use both the CD and MAC options you must only use the CD option.
Another user found and posted the trick he found to avoid all of the limitations :
To fix this error please follow the instructions below:
Step 1: Please go to www.turbotax.com
Step 2: Then click on the Do It Yourself Tab on the top menu bar
(The menu bar is located beside intuit TurboTax logo)
Step 3: Select Doing your taxes with a CD download
Step 4: Then click the Access My Downloads link (the link sits above the question below)
Which TurboTax CD/Download product is right for you?
Step 5: After clicking Access My downloads - Log into your account or create a new account.
Step 6: click downloads
Step 7: Look for the link ENTER YOUR LICENSE CODE HERE in the paragraph below.
Step 8: Type your license code on the next screen. do not copy and paste the license code here.
This trick can be used again and again up to 5 times per liscense code.
