Co-WIN was specially designed by the central government to monitor and track the inoculation process.
India had launched its COVID-19 vaccination drive on Saturday, inoculating 1.91 lakh people on the first day alone with two vaccines: Serum Institute of India's Covishield and Bharat Biotech's COVAXIN.
The Union Health Ministry on Saturday admitted that the Co-WIN platform had faced glitches.
While some vaccination session sites saw a delay in uploading of beneficiary lists, some people who were vaccinated on the first day were not scheduled on the platform.
Ministry Additional Secretary Manohar Agnani said, "System performance of Co-WIN platform and speed was improved and is being further optimized."
'No major glitches were noticed'
States where the data for healthcare workers was not uploaded to the Co-WIN platform were advised to improve the process and upload details.
An official added, "No major glitches were noticed. Almost all functions were smooth. We're constantly looking at the operations to ensure that the platform is ready to bear a major user-load that will be there once it opens up for others."
Nearly 2 lakh vaccinated on Saturday
India is aiming to vaccinate roughly 3 lakh healthcare and frontline workers in the first phase of vaccinations, followed by 27 lakh people vulnerable to COVID-19 (people above the age of 50 years, and people below 50 years, but with co-morbidities).
On Saturday, 1,91,181 were inoculated in 3,352 sessions held across the country, according to the Union Health Ministry.
Most people vaccinated in UP
Uttar Pradesh vaccinated the maximum number of beneficiaries: 21,291 in 317 sessions across all districts.
Andhra Pradesh had the second-highest number of beneficiaries (18,412 in 332 sessions), followed by Maharashtra (18,328 in 285 sessions), and Bihar (18,328 in 285 sessions).
Odisha vaccinated 13,746 people, followed by 13,594 in Karnataka, 10,787 in Gujarat, 9,730 in West Bengal, 9,279 in Rajasthan, and 9,219 in Madhya Pradesh.