NSDL
Not able to login using id and password

Dear Sir

I had registered at this company's site which deals with income tax pan cards, tax credit, e-filing of tax returns etc. I have reset my password many times but whenever i try to log in, the site says that my id or password is incorrect. i have also sent a query at their site, but have not received any reply as yet. I need to view my tax credit as some deductors of tds may not have correctly filed my tds details. Please help.