>What is the real cause of this message
>"too many files open,,,"
>

It means that not enough file handles are permitted for the environment. If no real mode drivers are in use, the entry FILES= in CONFIG.SYS controls the maximum number of files open at a time under WIn9x, the value can't exceed 255.

If real-mode NetWare drivers using NETX or VLMs are in place, and the problem is occurring accessing NetWare volumes, the entry in NET.CFG or SHELL.CFG controlling the number of Novell file handles, FILE HANDLES =, detrmines the number of open files under NetWare only. In this case only, the number of files in FILE HANDLES = and the CONFIG.SYS FILES= are additive, and can't exceed 255. If you are using a protected mode (native Win9x) network driver, the FILE HANDLES = entry is meaningless, and the CONFIG.SYS controls the total pool.