The number of files opened in Accelerated mode exceeded the number of buffers available in Btrieve's cache. In client-based versions of Btrieve prior to v6.0, you should reconfigure Btrieve both with a smaller page size configuration (to allocate more buffers) and a larger memory size option. You will not encounter this error either in v6.x client-based Btrieve, or in server-based Btrieve.