Finally i was able to file.
I had spent month and a half wrestling with customer support, 50 plus hours on phone and finally after going through creation of 2 additional online accounts and attempting wiith 2 different versions of desktop
First the bad news - once you encounter this error and if there is no way to clear and start over or upgrade, the account is mostly likely a junk for this year filing as they cannot clean it up for you.
Here is my experience -
After importing almost 5k brokerage transactions and connecting coinbase pro api to turbotax, i decided to carry on next day. The next day "pick up where i left off" button used to log me out, clicking on any link will log me out of online turbotax. Later turned into oops message. Wasted 7 days trying to resolve through customer support calls and sign up for updates.
Later they suggested desktop product. Problem with that is it cannot import the large 5k transactions, wasted 2 weeks trying to type in manually. Desktop version will start crashing somewhere around 1400 transactions but will let you continue, but after 2115 transactions it will crash every single time, also calculations will be messed up, Another problem is no crypto support for automatic imports, so returned it.
Started with creation of new account again as first account was toast for this year. This time around i got the oops error after connecting coinbase pro api with turbotax. So my guess is that is where the problem is. So second account is toast.
So created 3rd account, imported 5k stock transactions but for crypto entered them manually with summarized sales. you can use free link of cryptotradertax.io to generate excel in the proper format but still turbotax will reject it for some reason. so typed it and everything was fine i thought.
Finally because you use new account to file, they will put you on 48 hour hold when you attempt to file. So you have to wait for that hold to expire. Then file again. Now it will throw a new issue during transmission - unable to save return so efile will not be successful.
Again after contacting turbotax and after trying all the debugging steps, they will give you a desktop version for free to try but that also will crash when you attempt to file due to large file size.
Finally , the only way to solve is note down the calculation of stock sales from earlier import (proceeds,costbasis,adjustments etc) and break it down into 30 or so equal transactions and type it in manually and delete the imported 5k transactions. This was done with a tax expert as a last step as turbotax cannot handle 5k transactions (even though it says 10k) and causes the return file to become big which will prevent you from efiling or even printing for mail return.
Finally file size issue resolved, 48 hour hold on new account is resolved, oops error is resolved and able to submit.
i had also gone through mac, windows, chrome ,edge ,safari, phone app, wireless, wired connection, clearing cache cookies, restarting modem, trying through hotspot connection, answering questions and convinving them it is not my internet, no popup blockers, no firewall blockers, trying out manual mail filing (errors on download) etc. tried online and desktop versions. All this because customer support will want to go through those steps no matter what for making sure it is not something else. so after all that pain , they were convinced and finally agreed it is a file size issue and they have a problem with large stock transactions... Hope this helps in case you are waiting still trying to find a solution.
