You have not maintained offline settings for attachmnet download under "Attachment Download" tab, yet you see the attachmnet is available when you sync and go to offline.
Reproducing the Issue
Let us suppose, we have Sales Order attachment which is availale in offline mode as well.
- Go to Administrator -->Offline Settings.
Go to Attachment Download tab.
Make sure there is no record maintained for Sales Order under Download Document Types.
In the C4C app, sync and go to offline mode.
Check for the relevant Sales Order which had attachment.
You will notice that in the Attachment tab, you have the attachment file.
This is only a record of the attachment. When you click on the attachment name, you will get a message "Attachment is not available in Offline".
You will see a download button next to the "Delete" button in the attachment name. When you click it, the attachment will get downloaded.
Refer to KBA 2473944 , to know how to download attachments in offline mode.
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