I used 'Batch Output' to send an email with attached file in .csv and .iok format. An email can be sent successfully but cannot read the data in .csv file. There has no problem for .iko file. I tested to publish output via 'Email Output' and attached .csv. There has no problem reading the attached data.
version: 2.7-alpha b235 Attached file from Batch Output: OutputBatchMail.csv Attached file from Email Output: Email_output 2012-02-16.csv
I can confirm this is a bug. When selecting the "Email" output type the attached data would always be IOK format, even when specifying a different extension.
We have now fixed this bug. The fix will be available in tonight's 2.7 release.