I have input information into the "Mortgage Interest" section for rental properties 8 times. It shows the information, but still says "not started" on the edit page.

The same thing happened to me and more until I received a major turbotax update.  Don't know if this is the case for you or not, but if your software is not updating properly through windows and your systems protection software is blocking/may be preventing an update.  A temporary disable may help with a full update, but you can always go to the intuit/turbotax website and download the update directly from their site; it worked for me.

If you are filing with TurboTax online, let's do these steps: 

• Check your internet connection.  Try to log out and sign back in the program. 
• Clear your cache and sign back into the program.  To clear cache, click here: Cache
• You may also try a different browser.  
• Then try again. 

If you are referring to a rental situation, you should not enter any of the mortgage interest amount on your Schedule A.  You should ONLY enter the Form 1098 mortgage interest amount under the Rental.  The program will then allocate and pro-rate the mortgage interest between rental and personal based on the information of percentage of usage you provided.  The amounts should be allocated correctly on your tax returns.  ( Schedule E for rental and schedule A for personal)

If you own a rental property, the IRS allows you to deduct expenses you pay for the upkeep and maintenance of the property, conserving and managing the property, and other expenses deemed necessary and associated with property rental.  To learn more, click here: Rental deductions

To enter mortgage interest and point information on your rental ( schedule E), here are the steps:

In TurboTax online,

• After sign into your account, select Pick up where you left off
• At the right upper corner, in the search box, type in schedule e and Enter 
• Select Jump to schedule e
• Follow prompts

The same thing is happening to us (using TurboTax online).  Since it's the online software, I don't think the issue could be fixed by a software update.  All instructions I can find state that this expense (mortgage interest for a rental property for which we had no personal use) should be part of the Schedule E and not the Schedule A.  But unfortunately, TurboTax online is not giving us the option to enter in the Schedule E, but is instead of routing that mortgage interest to the Schedule A.

I am getting this same error using TurboTax Premier Online.  I have created the rental property profile and it allows me to enter the expenses: Real Estate Taxes, Mortgage Interest and Miscellaneous.  But Utilities, Insurance Premiums and Supplies just sit at 'Not Started'.  The value that is entered is saved when the  Start button is pressed so the values are being saved, just not applied as an expense.  So the Profit/Loss of the rental property is not being calculated correctly.

This is also happening to me. Has anyone figured it out?

I also have this error.  For me, it is affecting my entries for insurance premiums, repairs, mortgage insurance, and utilities.  No matter what I enter in these areas, nothing appears on the summary, and each still shows "not started."

UPDATE (fixed) -  Those entries appeared on the summary page once I removed my entry under "Expense - Real Estate Taxes," which I had also under federal deductions.  

I did everything.  Typical troubleshooting.  Cleared Cache and Cookies, switched browsers, updated Windows, rebooted, deleted the entire rental property, deleted the form, closed the program and restarted - multiple times in multiple ways and order.  Finally just downloaded the .tax file to my computer and switched to TurboTax Desktop.  Whala!  The error did not exist in Desktop.  That's my recommendation.  

This happened to me on the online version. I added a duplicate lender and amount, then deleted the first one. It worked!