We are experiencing problems with old DOS programs running on Windows NT 4.0 SP3 in a DOS Box. Sometimes if a program wants to access drive A for reading files the DOS program reports a read error on drive A:. If one retries, everything reads fine. The happens on several different DOS programs. We played around with some NT settings like application background time and also some System bios settings without any change. Does anybody has same experiences or some hints / solutions ?

There are two things to consider for your situation. The first is: What's on the disk's? If they are merely files that can be opened by an application existing on a DOS/Windows machine, try another machine - eliminating the possibilty of a floppy drive/disk problem. The other situation is complex: If you are trying to install/run a DOS application using NTFS, you may have a problem detecting hardware because NT does not directly "talk to" the hardware. NT uses a Hardware Abstraction Layer that seperates the NT kernel(NT translator) from the hardware. NT uses this method for stability, such that if a hardware conflict exists, it will not lock other applications running on NT - stable environment!