未正确配置 BackupDirectory 注册表项。当未提供完整路径名时，此项应指定存储磁盘备份文件的根路径。此路径还用于定位重新启动检查点文件以进行 RESTORE。

The BackupDirectory registry key is not configured correctly. This key should specify the root path where disk backup files are stored when full path names are not provided. This path is also used to locate restart checkpoint files for RESTORE.