Have run system cleaner on several PC’s was pleased at first until I found Java Engine would not work and had problems seeing external hard drive. Second PC totally crashed and never worked again and needed a clean install - mind you it was a former Redten PC with lots of bugs. Think this program works fine on stable PC’s :SMLR
Currently this release works well, which release do you have.
The previous CSC beta release I had resulted in system lockups almost anytime I clicked on it, from updating to etc. The error was Windows C++ Scripting Library. But this current beta release works smoothly with no problems.
I can gurantee this PC is not 100% and have had around 6 to 7 major crasher over the last 10 years where I could only recover C drive by loading In Place Upgrade via D drive.
Will be finally formatting after CIS is released with BoClean included (which should be a few months).
As for as Java, check to see if you have the latest JRE release. The last a week or two back was for bug fixes
UncleDoug
Then I suppose the new patent pending feature Safe Clean would be handy for you!
Ps. welcome to the forum 
Hello,
Would be very useful for me if you posted here the log files(all .txt files in the CSC installation folder). Also tell me what version of the application have you used? I think I will be able to answer you after this.