Hi,
I recently updated Anki Desktop to its latest version and Ankidroid to 2.17alpha5. I started to get issues with media files missing on Ankidroid, but also the “V3 Scheduler: “Invalid input: card was modified” while answering card” (sorry I can’t send links).
As well as database sync issues, having both Anki desktop and Ankidroid asking me to check the database and force a sync multiple times.
Since yesterday I can’t sync anything, having the “AnkiWeb encountered a problem. Please try again in a few minutes” error on Desktop and Ankidroid. I also get “Ankiweb : Bad Request” when I try to visit Ankiweb via browser.
I tried starting without addons, reinstalling, using a different browser, connecting with a different internet provider, with and without VPN.
If you download https://sqlitebrowser.org/ and use it to open your collection file, you should be able to fix the problem by editing the dconf column in the col table, and replacing the two null values in fsrsWeights with 0. Make sure you make a backup first, and regenerate the weights of your ‘main’ preset afterwards. I can’t think of a reason why this would happen; please let us know if it crops up again.
I would sometimes get an error like this if I was reviewing a card right at the end of Anki’s day.
In Tools / Preferences / Review, you have “Next day starts at: _____ hours past midnight”. So if I started reviewing a card a few seconds before the end of a day, and then marked it Good a few seconds after the end of the day, then this error would appear.
If by any chance this is what happened to you, then the solution might to be change “Next day starts” to some time in the middle of the night while you’re sleeping.
Stability being NaN looks like a bug in FSRS. If it remains NaN after making a tiny change to one of the weights in the deck options and saving, please indicate the card in question and I’ll try to reproduce it using your AnkiWeb collection.
