If you are upgrading to Daedalus 4.2.0 from version 4.0.5 or older, verifying the blockchain can take from 30 to 90 minutes.
Daedalus 4.1.0 and newer include a new version of cardano-node. Therefore, if you are upgrading Daedalus from version 4.0.5 or older, it can take from 30 to 90 minutes to verify the blockchain. This is due to DB migration on the first startup after the update. The migration can take from 30 up to 90 minutes (possibly longer) depending on your CPU.
Learn more: Cardano Node 1.26.1 Release Notes
[Trezor issue] When using Trezor T with a passphrase, user needs to confirm the passphrase several times
Due to an issue with the latest Trezor firmware, users need to confirm their passphrase several times when unlocking the device and accessing their wallet. This does not affect those who only use a pin code. Please note, the latest Trezor firmware is required for Catalyst Voting. If you use Trezor T with a passphrase and plan to register to vote in Daedalus/Yoroi/AdaLite, you will need to confirm the passphrase several times. The Trezor team is working to resolve the issue.
If your problem is not listed here...
For assistance, please submit a ticket to the IOHK support team from the Help menu in Daedalus, or by using the submit a request form.