If you receive a message indicating that Windows NT has no more available PTEs (System Page Table Entries), you may have manually altered the SystemPages value at:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Memory Management

This type REG_DWORD entry has a default of 0, which causes Windows NT to calculate the optimum number of PTEs reserved for mapping I/O buffers, and other systems information, into the system address space. The algorithm uses the platform type and available memory to calculate the number of PTEs.

If you manually set the SystemPages, which has a maximum decimal value of 50000, you prevent Windows NT from performing this calculation and automatically adjusting the number of PTEs based on available memory changes.