I am trying to export a SSRS report into Excel xlsx version. An error message pops up when I try to open the file saying "We found a problem with some content in the xlsx file". There are page breaks on the report. The Excel xls version works fine creating separate tabs at each break but the xlsx version errors out while opening the report.I have attached the RDL file and exported xlsx file for your reference.
Thanks for providing us sample RDL file and output XLSX file.
We observed MS Excel displays an error message “Excel found unreadable content” when opening the exported XLSX file into it. The issue looks to be related to merged cells. I have logged an investigation ticket with an id “SSRS-40233” for your issue. We will look into it soon.
Once we figure your issue out or we have some other update on it, we will let you know here.