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This web service renews an active lock that was acquired using PwsAcquireProjectorLocks. Locks are valid for a set amount of time (as a means of avoiding stale locks and the related problems). You can specify how long the lock is good for (up to 1 day) when acquiring the lock. If you have acquired a lock and intend to hold onto that lock for a significant amount of time (perhaps longer than the requested period of time), you should periodically invoke this service at an appropriate frequency to prevent your lock from expiring.
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