Currently the export creates XLS files, but the current Excel expects XLSX files. I have of course tried just to change the extension of the exported file, but result is that excel cannot open the file.
Using Xls will allow Excel to open the file, but will warn when opening the file.
Are there any plans for upgrading the TIWADVWEBGRIDEXCELIO component ?
There are currently no plans to add XLSX support in TIWAdvWebGridExcelIO.
You might want to consider using Flexcel to do XLSX export.
Note there is no dedicated grid export component available to do this so it will most likely require a lot of extra coding.
More information can be found on the Flexcel product page and if you have any further questions about XLSX export you can post those in the Flexcel forum.
I just checked the homepage and read about Flexcel and it definitely look like worth looking into.
However, I can't see that it is for IW as well as VCL and FMX. Could I use it with IW. My project is using IW and the TIWADVWEBGrid. Will it be possible to combine that with Flexcel ?
It won't be possible to use Flexcel in the same way as TIWAdvWebGridExcelIO but it might provide a workaround for features not supported there.
For specifics, please post your question in the Flexcel forum (where the responsible developer can answer in more detail) or you can also use the support form: https://www.tmssoftware.com/site/support_mail.asp