@Anonymous
I would request you to try and post your question in English so that, more people can understand and chances of getting an answer will be automatically increased.
I have translated your question and what I understood is your rules and forms have been disappeared after you migrated from Inventor 2020 to 2021. Correct me in case I misunderstood it.
I assume that you must be talking about external rules and global forms and not the document-specific rules and forms. In that case, I would advise you to check your Inventor project and its settings first and if they are ok, you can go to Tools>Options > iLogic Configuration, and select the directory from there which contains your rules.
I have created a screencast video to make it easier. Kindly have a look.
https://knowledge.autodesk.com/community/screencast/4de1ee58-5708-4098-b7e4-63255aae0e46
I hope it helps.
If this has answered your question make sure you accept this as a solution.
Regards,
Dutt Thakar
If this answer has solved your problem please ACCEPT SOLUTION and hit like if you found it helpful..!
Regards,
Dutt Thakar
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