I have a table and I download it with the built in Export button. But when I take a look at the Hex for the first 8 bytes of the file (just as phpSpreadsheet does when looking for the OLE signature), it is not there! This means I cannot upload the data that Grocery Crud has exported back into my GC application. I am using phpSpreadsheet since phpExcel was deprecated. It took a while where I couldn't imagine why the xls file created by GC could not be used by phpSpreadsheet. phpSpreadsheet looks at the first 8 bytes of an xls (or xlsx) file to determine if it is real. I don't know why it checks this again since it already checked the MIME, but whatever.
I figure if you could point out the code that does the creation of Export I could figure out how to get the OLE signature onto the front of it. How can I fix this? My plan is to have a user export their crud to their own PC so that they can edit/maintain it in Excel and then upload it back to GC where i will merge it with the existing table. The table can be pretty large with up to 300 records.