Vsphere 6.0U2 -- why frequetly shows that two of my VMs are reconfigured in Recent task list, how could I avoid this?

I'm using Vsphere 6.0U2, I installed some virtual machines with different Windows versions and I use 2 of them as VMware Horizon View agents. For a long time I see that 2 of the VMs are

reconfigured frequently in vsphere console Recent task list like below:

Could anyone tell me why this happens and how to resolve this? Thanks!