Either through UIDAI's website orby sending an SMS to UIDAI on 1947The Unique Identification Authority of India ( UIDAI ) has introduced a feature to lock and unlock your Aadhaar number. The move has been taken to further strengthen the privacy and security of the Aadhaar numbers of the individuals.Once you have locked your Aadhaar number, then authentication services using any method, i.e., demographic, biometric or OTP (one-time password), cannot be done using Aadhaar number. Therefore, you will have to use the 16-digit virtual ID for Aadhaar to undertake any authentication services for KYC purposes. You can use your Aadhaar number for authentication services only after you unlock your Aadhaar number.Before you lock your Aadhaar number, remember you must first generate your virtual ID. Remember your mobile number must be registered with the UIDAI's database to generate your virtual ID via SMS.There are two ways to lock or unlock your Aadhaar.If you wish to lock/unlock your Aadhaar number through UIDAI's website, follow the steps below.Step 1: Visit www.uidai.gov.inStep 2: Click on 'My Aadhaar' tab and under the 'Aadhaar services', click on 'Aadhaar lock/unlock'.Step 3: Select the option 'Lock UID' and enter the details - Aadhaar number, name as per Aadhaar records, pin code and security code.Step 4: Once these details are entered, click on 'Send OTP'.

Source: Economic Times May 16, 2019 05:00 UTC