We are afraid, you are using very old version and we only fix the issue in most recent version only.
However, please try this code and check if it makes any difference and works for you.
C#
//Save file and send to client browser using selected format
if (yourFileFormat == "XLS")
{
workbook.Save(HttpContext.Current.Response, "output.xls", ContentDisposition.Attachment, new XlsSaveOptions(SaveFormat.Excel97To2003));
}
else
{
workbook.Save(HttpContext.Current.Response, "output.xlsx", ContentDisposition.Attachment, new OoxmlSaveOptions(SaveFormat.Xlsx));
}
HttpContext.Current.Response.End();
Cookie Notice
To provide you with the best experience, we use cookies for personalization, analytics, and ads. By using our site, you agree to our cookie policy.
Enables storage, such as cookies, related to analytics.
Sets consent for sending user data to Google for online advertising purposes.
Sets consent for personalized advertising.
Cookie Notice
To provide you with the best experience, we use cookies for personalization, analytics, and ads. By using our site, you agree to our cookie policy.
More info
Enables storage, such as cookies, related to analytics.
Enables storage, such as cookies, related to advertising.
Sets consent for sending user data to Google for online advertising purposes.
Sets consent for personalized advertising.
Cookie Notice
To provide you with the best experience, we use cookies for personalization, analytics, and ads. By using our site, you agree to our cookie policy.
More info
Enables storage, such as cookies, related to analytics.
Enables storage, such as cookies, related to advertising.
Sets consent for sending user data to Google for online advertising purposes.