F2 in UDF cell with XLL not loaded breaks dependency tree?

[Matt Olenich]

1)  If I open XLSX without the XLL and hit F2 in one of the UDF Cells and save the XLSX and close excel. There are many cells using ExcelDNA UDFs.

2) Reopen the XLSX and then add the XLL ... and hit CtlAltF9 ... all cells recalculate except the one I used F2 on in step 1. It does not recalculate - unless I enter the cell and hit Enter.

3) Opening XLL fiirst and THEN the XLSX from step 1 ... no problem all cells recalculate with CtlltF9

Its as if using F2 on a UDF cell when the XLL is not available removes it from the dependency tree.

Can anyone explain or suggest a workaround other than telling users to start XLL first :)

Apologies - new to this group and did my best to search on F2 / Dependency Tree.

Matt