Hi, I need to state first that I am using w2000 SP5. This is a clean install, with no male ware. I understand that the OS is not supported. But, my other computer has a defective motherboard and unable to replace it now. I am using the last version of Firefox that was available for w2000, ( ver 11.0 ) I have modified Firefox NOT to UPDATE plugins. (Because new plugins don't; work in W2000.Firefox 11.0) I have installed the last version of Flash that works in W2000 also. ( fp_10.1.102.64_and_9.0.289.0_archive ) All works as normal. No crashes. No issues. Except, that the install magically disappears as a plugin from Firefox. It disappears 3 or 4 times a day. Usually after I open Firefox a few hours later. But, it is still in installed Programs list on computer. I have been re-installing it every time, which is VERY annoying. I have disabled Flash from automatic updates also. There must be something that is checking to install a new version, and deleting my current install. But, I can't find it. I have tried many versions of flash, and all do the same thing. So, I believe the problem is in Firefox. I am posting my problem at Adobe also. Please help me. TIA