listgrid.exportClientData() gives empty Excel files

[rpoyner]

Using: SmartClient_v111p_2017-11-27_PowerEdition

I'm hoping to export formatted data from a listGrid to an Excel file. Currently I'm able to use either exportData or exportClientData to generate csv files. However, with exportAs:"xls" or exportAs:"ooxml" I get back a small Excel file that has no data in it.

The listGrid:

isc.ListGrid.create({
ID:"roomReportGrid",
autoDraw:false,
autoFetchData:true,
dataSource:"roomReport",
canEdit:false,
showFilterEditor:true,
initialCriteria:{active:1},
sortField:"roomNumber",
showGroupSummary:true,
showGroupSummaryInHeader:true,
groupByField:"roomNumber",
groupStartOpen:"all",
showAllRecords:true,
height:550,
width:"100%",
fields:[ .............

The dataSource is a server-side mysql data source, which works well enough to populate the grid with the expected data.

Thanks in advance.
RP

[rpoyner]

Found the problem. I somehow had 2 vertions of the various poi .jar files in WEB-INF/lib both the correct 3.17 versions and stale 3.14 versions. Deleting the 3.14 versions made the download sort-of work. I had been hoping that the Excel file would include the summary rows, but that seems to not be the case.