Can you please provide more information about your problem? What happens when you try to Auto-Fill? Are you using TurboTax Desktop or TurboTax Online?

I am using Turbo Tax online.  I have used it for years and Auto Fill has always worked like a charm.  This year it is only downloading my Pension slips: T4A - employer, CPP, etc.  but none of my Investment related slips: T5's, T3's, T5008's, T11035 stuff, etc.  All these same Investment related slips Auto Filled last year no problem. 

Are the T3 & T5 slips showing up in your CRA MyAccount? If not, you'll have to contact whoever is issuing the slips and ask when they will be available.

If they are in your MyAccount, how many are there? 

Only my T4A, OAS & CPP slips are available on the CRA site.  All my T5's, T3's etc. are missing.  I have paper copies of all of these from my providers and they have advised me that all have been provided to CRA electronically by the February 28 deadline.  Why isn't CRA showing them?  It is March 31st.  Has Turbo Tax been advised of any problems the CRA is having?  If so I suggest you investigate this issue on behalf of your customers and advise them proactively instead of us tying up you Customer Support lines.

Yes, we did receive some issues reported as yours (not many). It's an issue on CRA's end. TurboTax can only fetch the information that CRA has. We have informed the assigned department, and we really appreciate your feedback.