RadTreeList's Excel export engine doesn't work in medium trust.
Posted on:19 Nov 2015 14:17
We will not fix this because of the following reasons:
- BIFF format is considered to be outdated (legacy from 1987)
- Partial trust is deprecated in .NET Framework
- Dependencies on unmanaged code
Our recommendation would be to use the XLSX format instead. It is supported by all major controls that support BIFF (RadGrid, RadPivotGrid, RadTreeList).