I also started having this trouble of TT crashing on starting. Here is what I remember the sequence of activity. I had downloaded the Premier version. Prepared taxes for myself, my son (Federal and CA States), then prepared for my daughter Federal & WI state. I was going between all three taxes back and forth and while I Was preparing my own taxes, since this was the first year I was going to prepare for a home based business we had started, I upgraded the version to Business. When I was ready to transmit my daughter's taxes via e-file, I went to the Intuit site to pay the $24.99 for the second state (WI). I paid with my CC and then at completion of payment instead of continuing where I left off in TT, it crashed at that point. After that it started crashing again and again even when I was just reinstalling (without deleting all the relevant files). Then I went thru all the files related to TT2019 under different folders like Cache, Cookies, Application Support, Webkit etc. Initially, I was thinking that in order for me to restore the downloaded version after reinstallation process to the business version, I have to save some of the files and restore them back to the file system and so I saved couple of files to my desktop. Then deleted all the files and reinstalled. After this when I open the app it still would crash. Then I thought perhaps the files on my desktop are still being seen by the installer and perhaps it was crashing and deleted them as well and tried reinstalling opening app. Still it crashed. Finally I realized that the Trash Bin was not being emptied and had all the files deleted thus far. Then when I completely deleted everything including Trash Bin and reinstalled and started the app, it came up and was able to open my previously prepared tax files. However one small issue still lingers - that is now when the app comes up, it shows a error report screen which needs to be sent to Intuit by clicking on "Send Report". When I click on that Send Report, it would crash again but if I just decide to close that error window the app will stay open. It took almost one whole day to get to this point.
What is surprising and frustrating to me that this must be such a major issue that Intuit Engineers must be working on and patching the product by now if I see some three on this going on since January but they don't seem to care to work on any patches to this issue. When I called the support desk the Product Support people don't even try to go over this symptom as a "Known Issue" either to suggest a work around!!!
