1574664 - BPC 7.5 NW (Outlooksoft) opening .xlsx .docx files from content library shows a warning about file format difference with the file extension

When opening a file (*.xlsx, *.docx) from BPC Content Library the following warning is shown.

The file you are trying to open, 'ShewFile.aspx', is in a different format than specified by the file extension. Verify that the file is not corrupted and is from a trusted source before opening the file. Do you want to open the file now?

Image/data in this KBA is from SAP internal systems, sample data, or demo systems. Any resemblance to real data is purely coincidental. 

• SAP Business Planning and Consolidation (BPC) version 7.5 for the NetWeaver (NW) platform - server and client.

BPC, Excel, does not open, error, warning, extension, SBOP PC. , KBA , EPM-BPC-NW-WEB-CON , Content Library , Problem