Custom functions not registered when Excel is launched via COM Automation; any recalculation causes #NAME! or #VALUE! error. about office-js

[gmichaud]

I have updated the bug description above with the updated sample

Here's an updated set of test macros:

ExcelAutomationCustomFunctionsAdditionalScripts.zip

I have also simplified the test workbook down to a single custom function

• Test.vbs: workbook opened before Excel application is made visible -- custom functions are not registered at all
• Test2.vbs: workbook opened after Excel application is made visible -- custom functions are registered and working
• Test3.vbs: workbook opened after Excel application is made visible, but recalculation triggered too quickly -- #VALUE! error displayed in all the cells

I inspected the side-panel console and our telemetry and we don't see anything being logged, so assuming function registration is not yet completed at this stage. It sometimes happen that Excel triggers a recalculation on file open; if custom functions are involved, the #VALUE! error will be shown to user as well. Users can then manually force a recalculation, but it looks like a bug to them.

I think Excel should defer calculation or keep waiting until the add-in has been fully initialized in these scenarios.

[shanshanzheng-dev]

Hi @gmichaud Thanks for reporting this issue, we'll take a look and report back if we have a suggestion for you.