My question is what if it causes issues in the computer? Should i use the back up feature? How do I use the back up in the situation of a failure.
Hello and welcome to the forum. Instructions for using the back-up function are found here:
I've never had any problems cleaning the registry with CCleaner, but there's always a first time. When you go to delete the registry entries, don't be tempted to do everything at once. Check off small batches of entries for deletion, save your backups, and keep all the backups in your Documents folder until you're absolutely sure that Windows or none of your other programs has a problem.
A small item: You should post any future questions about CCleaner in the CCleaner section of the forum. Makes it easier for other members to find them.