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3rd Party AddIn problems


I am evaluating Aspose.Cells for a program we are currently developing for a client. So far, I really like the product, however, there is one problem we have run into. I will try to explain the situation the best I can.

The client has a spreadsheet (xlsx) that they maintain internal to their company, that they dont want to expose to their customers. So we are making a web application that loads their spreadsheet in the background, and gets data/values out of it as well as we want to be able to put data/values into it and then grab the results etc…

Within this spreadsheet, our client is using several builtin functions, such as FORECAST, VLOOKUP, etc… BUT there is one function they are using from a 3rd party AddIn called, TriLookup.xla. This addin is made by a company called TriMill. So, the problem is, I do not see how to get Aspose.Cells to load and use this 3rd party AddIn, when it loads this clients spreadsheet.

Thanks for any help or information you can provide,
Ed Barlow
Senior Programmer


Well, Aspose.Cells does support Excel’s add-in functions e.g MCORRELS, REGRESSN etc.
Could you provide us the TriLookup.xla and any other relevant/dependent file(s), descriptions etc., we can check it soon.

Thank you.

Hi Amjad,

Thanks for the quick reply.

The TriLooup addin is available here:
At least that is an evaluation version. The version I am using is a registered version, that does not have a popup when starting Excel. So I am worried that maybe you trying to test with the Evaluation version is just going to cause more problems.

An example of how its being used:

Given a 2d grid of data, for example in $V$26:$AG$35, and then this formula assigned to another cell:


Where UCUT, REACH, LOC, and CUTDIA are Named ranges/values in the Name manager, and T2LOOKUP is the function in TriLookup.xla. And in Excel, when the links are not updated, T2LOOKUP is replaced with ‘C:\Program Files (x86)\Trimill\TriLookup\TriLookup’!T2LOOKUP(…

I will see if I can put together a sample worksheet for you to test if needed, unfortunately I cannot give you the real spreadsheet.

Thanks, Ed


We appreciate if you could give us sample Excel file implementing your add-ins function in a sheet, you can use dummy data if you want.

Also, I have logged it with an id: CELLSNET-30335. We will look into it if we can support it.

Thank you.

Here is a sample Excel file.

It has 3 Named Values that you can change in cells C18, C19, and C20.

The cell with the formula calling T2LOOKUP is in B2.

Thanks for your help with this,



Thanks for the sample Excel file.

It may help us for investigation.

Thank you.


We could not calculate ‘C:\Program Files (x86)\Trimill\TriLookup\TriLookup’!T2LOOKUP() method.

If you simply set the formula as =ABS(IF(UCUT=“NO”,0,T2LOOKUP((REACH-LOC)/CUTDIA,CUTDIA,V26:AG35,-8,-8)))

You can try Workbook.CalculateFormula(bool ignoreError, ICustomFunction customFunction) method and implement T2LOOKUP function in ICustomFunction