One file can be opened by Aspose and the other cannot


I have uploaded 2 files to the forum fdmem.xls and fdmem2.xls. fdmem.xls fails on this call…


with the error…

System.Exception: Invalid file format.
at Aspose.Excel.av.a(MemoryStream A_0)
at Aspose.Excel.av.a(String A_0)
at Aspose.Excel.Excel.Open(String designerSpreadsheet)
at Inginix.Common.UI.Controls.DataLoadControl.LoadSites(Int32 docID) in …

I opened fdmem.xls and saved it as fdmem2.xls but with a different option in Excel. fdmem2.xls can now be opened.

It seems fdmem.xls might have been saved with an earlier version of Excel. What versions of Excel are supported? I think fdmem.xls should be a late enough version to be ok. Can you tell me why it cannot be uploaded?



Here is fdmem.xls.


Here is fdmem2.xls.


fdmem.xls is Excel 2002
fdmem2.xls is Excel 2003


Aspose.Excel supports Excel97 and above version of MS Excel.

fdmem.xls is saved as “Microsoft Excel97 - Excel2003 & 5.0/95 workbook” format and fdmem2.xls is saved as “Microsoft Office Excel Workbook” format.

Aspose.Excel now doesn’t support the first dual-format. Please save all your designer files as the second format.


Is there a way to somehow check the format so I can report back to the user that they are using an unsupported file format?


Currently you can try-catch the exception and report back to the user.

Later I will embed it into Aspose.Excel.
How about the following approach: Open method return false if meeting a invalid file format?


I am having the same issue. One xls opens fine and another does not. As a test, I saved a working xls as the duel format metioned above and it still worked. We are using version of the Aspose.Excel dll. How do you get the version an excel file was saved in?



Could you please upload the file which cannot be opened?

In previous version, Excel95 is patially supported, so dual format is supported. However, we found fewer and fewer users use Excel95 and many Excel95 advanced features are too complex to support. So we give up Excel95 support now.

You can also try our latest hotfix at


Great, I’ll send the file. What email address should I use?



Hi Mike,

You can upload your file here. When you reply the message, you can see “Attachment” below.

However, if you don’t want to make your file public, please send it to


I tried to send you another excel file that is raising the same exception to the given mailaddress, but I got the attatched standard-answer.

Because the file is confidential, I can not add it as a Attachment here.


Tobias Roemer

Dear Customer,

To provide more prompt support, since May 8, 2005, we have merged email support into Aspose.Forums. More info please check

Now we’ve got your email sent to but we need your cooperation to re-post your questions to as is not attended by Aspose any more. After you have posted your question in the forums, we will reply to you over there.

Sorry for any inconvenience and we always appreciate your business. Team


Dear Tobias,

Please check
Your attachments can be seen and downloaded by our developers only. No other customers or visitors except you can see or download your attachments.

And which version are you using? Have your tried the latest version at