Unfortunately I have lost the password & seed phrase of the metamask chrome extension. I have access to browser & extension file installed on located on PC.
Is there anyway to decrypt password from the extension files, so i can login again to metamask?
No. Sorry, there's no way.
Having a backup of seed phrase is required to recover the wallet. If you used a password that you generated by yourself (Not a random one), you can try to remember it. There's no limit on how many times you can try the password. See this Metamask page for important infos on how to handle password and seed phrase : https://metamask.zendesk.com/hc/en-us/articles/4404722782107-User-guide-Secret-Recovery-Phrase-password-and-private-keys
