I am trying to send xlsx attachments through an exchange server and whenever I receive the message the exchange server has stripped out the xlsx file and replaced it with a txt file with contents "This attachment was removed.". I have tried both SMTP and OWA connection methods.

One would blame the exchange server for doing this, however I can send the exact same xlsx file through Outlook and through a competitors automation software without the file being stripped out like this. Therefore I think it has to do with VisualCron not formatting the email correctly, perhaps with correct MIME types on the email attachment.

Has anyone seen this issue before?

I am trying to send xlsx attachments through an exchange server and whenever I receive the message the exchange server has stripped out the xlsx file and replaced it with a txt file with contents "This attachment was removed.". I have tried both SMTP and OWA connection methods.

One would blame the exchange server for doing this, however I can send the exact same xlsx file through Outlook and through a competitors automation software without the file being stripped out like this. Therefore I think it has to do with VisualCron not formatting the email correctly, perhaps with correct MIME types on the email attachment.

Has anyone seen this issue before?

Hi Adam,

Which version is this on? I can not seem to reproduce this issue.

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Can you send any attachments in this job? I would try to attach a sample text message that is blank. If that gets removed too then it has to be exchange or maybe some security device or software that looks for attachments. Where the server is or how it interacts with exchange may be different than your other software you tried

I second Joey S's suggestion. Please try that, and let us know the result.

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Hi,
I am using VisualCron 8.5.5

I have done some further troubleshooting and have worked out that it does not seem to be an email send issue, it seems to be an issue with the way VisualCron generates Excel files.

The job which has the issue runs a query from a database and populates an excel file with a number of worksheets. It then sends this excel file as an attachment.

I set up a test job which sends both a VisualCron generated excel file and a file saved from Excel 2016. The VisualCron Excel file gets removed whilst the other Excel saved from Excel stays intact. So it seems the issue is related to how VisualCron is generating the Excel files which is leading to Exchange thinking they are corrupt somehow.

Attached is both Excel files for your reference.



Thanks
Adam.

Your file seemed to open fine for me so I am not sure what your system is seeing to disallow.

I had a few SQL jobs setup already so I added an "Excel - Create" task and and an email task and tested a scenario on my own end.

I used the default settings for "Column" and you can see, in my attachments the other settings I have. I did not do anything out of the ordinary and the excel and email tasks worked as expected. I bet your IT department has a way to see what, in that file, is causing the error when it hits your exchange server.

Hi Joey,
Thanks for checking this. Yes, thats exactly how I am generating the excel file too.

Our Exchange server team have looked at the issue and the only suggestion from Microsoft is to switch off the "Attachment filtering agent" which blocks invalid attachments, but they arent willing to do this for obvious reasons.

Thanks
Adam.

I wonder if this would help...https://support.microsoft.com/en-us/help/2855809/email-message-attachments-are-removed-incorrectly-on-an-exchange-serve

Also, If I was you I would just send the file without an extension (or maybe substitute 'xlsx' with 'csv') . If that passes then you have some ammunition, so to speak, when going back to the exchange administrator.

Hi Joey,
If you read the suggestion on this URL, it is suggesting to disable the attachment filtering completely. This means potentially dangerous attachments will not be blocked anymore. We cannot disable this as suggested.

There is no point checking other file extensions when an xlsx file saved from Excel passes through fine, but a VisualCron generated xlsx file get blocked. Also, this Excel has to be sent as a proper excel file attachment as we have customers who receive these emails. We cannot ask them to change file extensions etc - that is unprofessional.

Theres only 2 solutions to this problem - either VisualCron find and fix the issue or I use another app to generate the Excel file with my data so Exchange server doesnt think the excel attachment is corrupt. I will have to use the latter for the time being in any case.

Thanks
Adam.

Hi Joey,
If you read the suggestion on this URL, it is suggesting to disable the attachment filtering completely. This means potentially dangerous attachments will not be blocked anymore. We cannot disable this as suggested.

There is no point checking other file extensions when an xlsx file saved from Excel passes through fine, but a VisualCron generated xlsx file get blocked. Also, this Excel has to be sent as a proper excel file attachment as we have customers who receive these emails. We cannot ask them to change file extensions etc - that is unprofessional.

Theres only 2 solutions to this problem - either VisualCron find and fix the issue or I use another app to generate the Excel file with my data so Exchange server doesnt think the excel attachment is corrupt. I will have to use the latter for the time being in any case.

Thanks
Adam.

I am not sure what you mean there is to fix. The Excel file is not corrupt. This is the Email server rules blocking in this case.

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Hi Henrik,
If its the email server rules, then why is it possible that an xlsx file saved from Excel or SSRS is able to be sent and received successfully, but a VisualCron generated xlsx file is treated as "invalid"?

What I have now done to work around the issue is generate a xls file from VisualCron and add a command line step which executes excelcnv.exe which will convert the xls file to xlsx format before its sent via email.

Thanks
Adam.

Hi Henrik,
If its the email server rules, then why is it possible that an xlsx file saved from Excel or SSRS is able to be sent and received successfully, but a VisualCron generated xlsx file is treated as "invalid"?

What I have now done to work around the issue is generate a xls file from VisualCron and add a command line step which executes excelcnv.exe which will convert the xls file to xlsx format before its sent via email.

Thanks
Adam.

I guess it could be a number of values that finally decides it is spam - maybe it is a combined score with sender ip, sender email, recipient email, subject and actual content in the file. We have not created our own Excel engine for creating but are using a well known engine so I doubt there is anything wrong with that.

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