Promble when I set sheetName=“sheet1”，and download in browser is ok， but when I open it in my excel, it say my file contains some error

[johnsGuo]

Describe the results you received:
here is my test code

package utils

import (
	"fmt"
	"github.com/xuri/excelize/v2"
	"testing"
)

func TestExportExcelUtil(t *testing.T) {
	t.Run("", func(t *testing.T) {
		f := excelize.NewFile()
                // if set "Sheet1" the xlsx will open ok in Excel, only use "sheet1" occur error
		sheetIndex := f.NewSheet("sheet1")
		f.SetActiveSheet(sheetIndex)
		f.SaveAs("test1.xlsx")
	})
}

it's running ok, but the xlsx file may occur error when open in Excel

Environment

go version go1.15.6 darwin/amd64
with github.com/xuri/excelize/v2 v2.4.0

[xuri]

Thanks for your feedback, which version of Excelize are you using? I've tested and it works well. Could you provide more details, code to reproduce this issue or a spreadsheet xlsx attachment without confidential info?

[johnsGuo]

go version go1.15.6 darwin/amd64
excelize v2.4.0

you can use my demo code to test, only when I set SheetName='sheet1' occur this problem.

[xuri]

Thanks for your issue, I have fixed this by letting the sheet names are not case sensitive for NewSheet, GetSheetIndex, DeleteSheet. Please try to upgrade the master branch code, and this feature will be released in the next version. When creating a new spreadsheet file, the default
worksheet named Sheet1 will be created, if you wanna change the name for it, you can using the SetSheetName.