Excel Crashes When Adding xll Reference

[steven price]

Hi

We have just updated out .NET ExcelDNA Addin Project to the latest ExcelDNA version from GutHub and successfully rebuilt our project.  However when we try and add teh addin to Excel by :- 

1 go to Excel -> Options -> Add Ins  -> Manage Addins -> Go  

2 browse to our debug folder 

3 select the projectname64.xll file 

Excel crashes. 

We have checked and are using the 64 bit version of Excel. We also tried the above steps using the projectname-Addin64.xll and projectname-Addin64-packed.xll files 

Any help much appreciated 

Regards

Steve