We have the exact same problem.
Although you can select Save As option and give the file a new name, the Save function returns with Error (1502) occurred during the action save.
Very annoying and have yet to find any information on this problem.
Any attempt to use the Save function produces this error. Whether it's a new file and we try to save or if we open an existing file and try to save.
We are running Windows XP Pro SP2, Office 2003 SP2 and Visio 2003 SP2. Running on IBM ThinkPad R52 Intel 1.8 Ghz and 512 MB RAM.
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