Tds revised return

Dear Experts,

I have 2 Queries related to TDS. 1st is How can we revised a return through traces if there are unmatched challans in the return ,without updated digital signature on the traces. 2nd is is there any other option for getting fresh user id and passeword from traces  if we forgot user id & password of traces & we also dont have any data to be filled in step 2 of forgot password option.

Thanks in advance.

Nitin Bhatt