Excel “External table is not in the expected format.”

Question

I\'m trying to read an Excel (xlsx) file using the code shown below. I get an \"External table is not in the expected format.\" error unless I have the file already open in

Answer 1

I recently had this "System.Data.OleDb.OleDbException (0x80004005): External table is not in the expected format." error occur. I was relying on Microsoft Access 2010 Runtime. Prior to the update that was automatically installed on my server on December 12th 2018 my C# code ran fine using Microsoft.ACE.OLEDB.12.0 provider. After the update from December 12th 2018 was installed I started to get the “External table is not in the expected format" in my log file.

I ditched the Microsoft Access 2010 Runtime and installed the Microsoft Access 2013 Runtime and my C# code started to work again with no "System.Data.OleDb.OleDbException (0x80004005): External table is not in the expected format." errors.

2013 version that fixed this error for me https://www.microsoft.com/en-us/download/confirmation.aspx?id=39358

2010 version that worked for me prior to the update that was automatically installed on my server on December 12th. https://www.microsoft.com/en-us/download/confirmation.aspx?id=10910 https://www.microsoft.com/en-us/download/confirmation.aspx?id=10910

I also had this error occur last month in an automated process. The C# code ran fine when I ran it debugging. I found that the service account running the code also needed permissions to the C:\Windows\Temp folder.

Answer 2

I know this is a very old post, but I can give my contribution too, on how I managed to resolve this issue.

I also use "Microsoft.ACE.OLEDB.12.0" as a Provider. When my code tried to read the XLSX file, it received the error "External table is not in the expected format." However, when I kept the file open in Excel and then the code tried to read it ... it worked.

SOLUTION: I use Office 365 with company documents and in my case, the solution was very simple, I just needed to disable the sensitivity of the document, setting it to "public". Detail: Even after saving as "public" the green check still remained marked in "Internal Use", but the problem remained solved after that.

Answer 3

If you still have this problem, then check your permissions, I tried many of these suggestions and my concrete problem was that the file that I wanted to process was under source control and the thread had no permissions, I had to change the entire folder permissions and it started to work (I was processing many files in there)... It also matches many suggestions like change the name of the file or check that the file is not loicked by another process.

I hope it helps you.

Answer 4

Ran into the same issue and found this thread. None of the suggestions above helped except for @Smith's comment to the accepted answer on Apr 17 '13.

The background of my issue is close enough to @zhiyazw's - basically trying to set an exported Excel file (SSRS in my case) as the data source in the dtsx package. All I did, after some tinkering around, was renaming the worksheet. It doesn't have to be lowercase as @Smith has suggested.

I suppose ACE OLEDB expects the Excel file to follow a certain XML structure but somehow Reporting Services is not aware of that.

Answer 5

the file might be locked by another process, you need to copy it then load it as it says in this post

Answer 6

Just adding my solution to this issue. I was uploading a .xlsx file to the webserver, then reading from it and bulk inserting to SQL Server. Was getting this same error message, tried all the suggested answers but none worked. Eventually I saved the file as excel 97-2003 (.xls) which worked... only issue I have now is that the original file had 110,000+ rows.