virtualbox.org

I am not sure if it is mainly from "Shared file"... When I click on "Devices - Shared Folder - Shared Folder Setting..." and it will pop up an error saying:

"The instruction 0x00000000 referenced memory at 0x00000000. The memory could not be written. Click OK to terminate the program"

I looked around here and similar cases, but not much help at all.

Initial I installed ubuntu 32-bit, but I have the same error even I am doing nothing it will pop up this error. Then I try the ubuntu 64-bits, and it looks like this error only comes out when I try the shared folder.

Any suggestion?

I'm afraid that the log file you provided is incomplete, and in particular is missing the important stuff after bootup. Even if the VM crashed there should have been an exception handler report in the log. Please make sure that the VM is completely shut down (not running, not suspended) when grabbing a log.

Also, please zip logs before attaching them, as this makes it fairly sure you won't hit the attachment size limit.

Finally, please confirm that this was a VirtualBox process error on the host (when accessing the menu you mention), not an error with an app inside your Linux guest (I notice that you posted in the "Linux Guests" forum).

For what it's worth: in my experience, crashes when accessing file open dialogs are not that unusual, and usually have to do with buggy shell enhancements software on your host which have nothing to do with VirtualBox. E.g. Bluetooth browser stacks, virtual VMDK driver etc. Address 0x00000 is what's called a NULL address (an address conventionally used to indicate "nothing is currently selected", and the crash indicates that a buggy something tried to process <nothing> as valid data.