Lost files when using free edition of cc cleaner

I was trying out the software and it gae me a report that if I removed certain files, my pc would run better. I showed a few files that were agreeably ones that I did not need, but is also showed others that contained files that I did not want to remove and in order to access that section I would be required to buy the product, so I did not. However, many files were 'lost', especially my income tax files and I could not find then to recover them. I need to recover these and don't know how. SInce i did not remove them, the program should not have touched them. Please advise asap. thanks.

. . . I would be required to buy the product, so I did not. However, many files were 'lost', . . .

CCleaner is free, and does not require payment for removing files.

From where did you get the program? If possible, post the url so we may investigate the source.