V5.27.5976 64bit Pro and Firefox 51.0.1 crashes on some settings in CCleaner Bug Reporting Posted February 25, 2017 FWIW, I have had this issue and identified that it also affects thye compact database option for Thunderbird - the Mozilla Email program too. I had to disable the compact database option for both programs to get CCleaner working again.
V5.27.5976 64bit Pro and Firefox 51.0.1 crashes on some settings
in CCleaner Bug Reporting
Posted
FWIW, I have had this issue and identified that it also affects thye compact database option for Thunderbird - the Mozilla Email program too. I had to disable the compact database option for both programs to get CCleaner working again.