My computer always promote a msg "Close programs to prevent information loss\n Your computer is low on memory. Save your files and close these programs.", since last time I set the virtual memory on drive D. So long as I open a little more app, some program absolutely will crash.
I go into virtual memory setting in advance computer option, there is only several MB virtual memory, but I had already allocate 3GB space of D partition to the virtual memory. What`s going on? does the permission cause this? Del pagefile.sys & restart system, not solved. even google at internet, no answer here.
When I view Windows Registry, I finally find where the problem is and the solution:
WIN+R then type regedit to open Windows Registry, continue to go forward [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management], seek out a Dword key named "PagefileOnOsVolume", modify its hex value to 1, at last reboot the computer.
It turn out Microsoft force the virtual memory to save in Drive protected by BDE(BitLocker Drive Encryption) for security reasons, so as to prevent confidentiality issues of data in virtual memory file when BDE is used to protect the OS volume. When set value of PagefileOnOsVolume to 0, it will disable this feature.