Same issue, I think it has to do with the number of slips TurboTax can handle. The CRA says you can download up to 500 slips at once, but when I try to load ~225 into TurboTax I get a very cryptic and unhelpful error message saying "Oops, we encounted an error".
A more helpful message would read "our servers only allow up to X slips to be downloaded, please manually enter all your slips"
An even more helpful option would be to download all but my T5008 so I don't have to manually enter everything. Then I can just combine my T5008s by brokerage to have just ~4 slips to manually enter.
I know this issue wont affect most people since trading 200+ times a year is uncommon but TurboTax should be able to support this for the extra $ paid to file investment products.
