There was a bug in some earlier versions. Please upgrade to any release - 13.67 or later - that falls within the six-month free period since your purchase.
Find them all here. Ignore any virus warnings.
For licensed users upgrades are free for up to six months from purchase date. After that, VP will continue to fully function but a fee is required in order to register the newest. Retain your old install file and registration info. If there's an issue, you can always revert.