Check for the simplest things first: Cable problems, jack problems, etc.

For instance, if anyone ever accidentally plugged a regular telephone wire into the ethernet jack of either the PC or the Empeg, then two of the eight pins are bent and it will only work intermittently.

Check your device manager in Windows and look for little yellow boo-boo icons (official microsoft name).

Do you get link lights on both devices?

Did you upgrade the Mark2 empeg with a Mark1 .upgrade file? That'll kill ethernet, too.

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Tony Fabris