Yes, Re-Registration of TAN is now provided by NSDL. Earlier only TAN Registration was possible, but now re-registration can be done. It is general question that why Re-Registration of TAN is required ?. Through below example it can be explained.
Answer of Question through Example :-
A Government/Non-Government Institution submit their e-tds/e-tcs return through a service provider named ABC e-tds Solution etc. After a gap of two or more years, it is found that ABC e-tds Solution has not submitted returns properly and deductor receives different type of letters from Income Tax Department. In such position through correspondence between deductor and ABC e-tds Solution, their understanding breaks and deductor decides not to continue return submission through ABC e-tds Solution.
Now deductor engages another service provider to submit their e-tds/e-tcs return. New service provide demands from deductor TAN Registration detail such as User ID and Password of the concerned TAN to resolve the notices received from Income Tax Department. Due to bad under standing with old Service Provider (ABC e-tds Solution), It is not possible to collect the User ID and Password from ABC e-tds Solution which was registered by him. In such condition, earlier there was typical procedure to get User ID and Password from Tin Center.
Through new system provided by NSDL, Re-generation system is too-much easy in the hand of Deductor. Just enter your TAN in Registration Form , a message will be appeared that "Tan is already Registered. Do you want to Re-register". Just click ok and re-register your TAN number through filing complete detail. Picture of Re-Registration of TAN is also given below more clarity.
Re-Registration of TAN (Click Here)