Step 3: Clean Out Your System Junk (Temporary Files and Folders) With Disk Cleanup (cleanmgr) Over time, your computer accumulates junk files from normal web surfing and computer use. If this junk isn't occasionally cleaned out, it can cause SuSE Linux 7.2 Professional to respond slowly or provides an ja-mac.jar error, possibly due to file conflicts or an overloaded hard drive.