I have installed VB5 into my computer and I have installed VB4 after that. Then, I need to remove VB5 from my computer. So, I use add/remove application icon from control panel. After I remove VB5 from my computer, some custom control was deleted and I can't use it in VB4. So, I try to remove VB4 and install again into my computer. An error message will be shown while it update system. Error message was like unable to regist Crystal report into registry. So, I try to check out with registry and delete Crystal report, it still not work. I have try to add crystal report and point the value for this key to crystl32.oca in system directory. It still unable to add crystal custom control into VB4. How can I solve this problem? Now, I can't use crystal custom control in my application and can't install it into VB4. Thank in advance.