In WSS 2.0, there’s an option to create a new list by importing an Excel Spreadsheet.
I’ve got Excel 2007 installed, and so after selecting the cell range of an .xls file I got this error message:
Method ‘Post’ of object ‘IOWSPostData’ failed
Searching for this gave me a possible solution
Because this particular SharePoint is still version 2.0, I figured that lVer = 2 was appropriate, and the good news is it worked.