Follow up Note: The MathNET DLL was compiled as a NET 3.5 vs NET 4.0.

That said, I am not sure that VS 2010 Beta 1 is correctly "dumbing-down" the actual DLL & Setup
files from 4.0 to NET 3.5.

wrote:

Using XL 2007; VS2010 and VB2010;

Created Chip Pearson's MathNET which works fine XL 2007 Vista w/NET 4
but not on my XL 2007; XP Pro; w/NET 3.5

On the XP Net 3.5 machine, I can see the MathNET (as MathNET.ExcelDivision and
MathNET.ExcelMultiplication) in the Excel Inactive Add-ins; plus I can place/remove a checkmark in
the Automation Input Box but I cannot make the Excel those referenced Add-ins Active.

Therefore, when in Excel, I enter "=DivideBy4(anynumber)" I get #Name?

In contrast, it works fine on my Vista Machine. (Note the VB was compiled with Com Addin as Visible)

Is this a NET 3.5 issue and/or an Excel issue? (BTW, I cannot install (RAM limitation) VS2010 or
VB2010 on the XP Machine I just transfer the files from the Vista Machine)

Any Thoughts appreciated

EagleOne

TIA Dennis