I think I will throw my hat into this ring as well. I am running CCleaner Professional ver. 5.77 on three machines. There is absolutely no problem on two of them, but on the third, a Dell G7 7700 with an I7 processor and 32 gig of memory, it appears in the System Tray at boot, but immediately unloads. The icon remains, but it the cursor passes over it, the icon disappears. Task Manager indicates that Ccleaner is not operational. If I later start Ccleaner, it seems to load and operate fine. There is something quirky here as it worked fine in the past, but something changed in February.