Hi there

Salesforce does not allow you to create PDF attachments in batch job.

This is work around to that.
https://developer.salesforce.com/forums/?id=906F0000000AlGoIAK

It works!

But As of Summer 15, Salesforce have implemented a critical update "PageReference getContent() and getContentAsPDF() Methods Treated as Callouts". Once enabled, you may get the rather uninformative error "(304497466)|FATAL_ERROR|System.CalloutException: Callout loop not allowed".

And so I have the problem described in this blog: http://codrspace.com/gwickman/callout-loop-not-allowed-error-when-using-getcontent-and-getcontentaspdf/

Can someone please help me get around this error or help with another way to create PDF attachments for emails in a batch job?

Thank you very much