The Canada-based doping watchdog said that the team was unable to extract the data because of issues raised by Russian officials that had not been mentioned in previous talks between them and WADA.
"The team was unable to complete its mission within the prescribed time due to an issue raised by the Russian authorities that the team's equipment to be used for the data extraction was required to be certified under Russian law," WADA said in a statement.
Providing full access to the lab by the end of the year was a condition of Russia's controversial reinstatement in September following a major scandal over state-sponsored doping.
But the Russians did not permit retrieval of the data dubbed "the missing piece of the puzzle" by WADA officials, who had said they wanted to review the data and have Russians retest any samples required by WADA by June 30 2019 as part of the reinstatement deal.
That agreement was assailed by athletes and organizations worldwide, an outrage that has dogged Russia and WADA as it bids to return Russian athletes to the full global stage.
The latest misfire could lead to a return to suspension status for Russia's Anti-Doping Agency.
The WADA team arrived Monday and had some access to the Moscow lab and made some progress in the process of extracting data to take outside of Russia, information vital to implicate or clear athletes in doping cases.
Jose Antonio Pascual, the doctor and independent expert leading the WADA team, will still prepare a report on the failed mission for an independent compliance review committee that meets January 14-15, when Russia's compliance status will once again be considered.
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