Hi @Prajwal_Raj ,
This is a known compatibility issue that occurs when chats created in an older version of Cursor (≤2.3) are opened after an update across major versions. The chat data is still stored locally, but a server-side session token needed to continue the conversation gets lost during the update because the migration doesn’t run automatically.
If that doesn’t work (the session token may already be unrecoverable depending on how old the chats are), you can still view and export your old chat content – you just won’t be able to send new messages in those conversations. Starting a new chat will work normally.
A community member posted a detailed technical analysis of this issue, and the team is aware of and tracking it.