This article was created in response to a support issue logged with K2. The content may include typographical errors and may be revised at any time without notice. This article is not considered official documentation for K2 software and is provided "as is" with no warranties.
A form contains an attachment control and this attachment control is connected to a SmartObject which points to a SQL table or stored procedure. The Attachment Control will stop working after a day or so. A restart of the K2 Server resolves the issue, but then it will show up again.
Unable to upload or download attachments in the Attachment control after a day of it working as expected.
This is a known issue that occurs because the SQL Column is a varchar which K2 interprets as a Memo type.
However, since this column is used for storing files, it should actually be a File type on the SmartObject. See the screenshot below.
Changing the SmartObject Property type that uses the Attachment Control from Memo to File will resolve the issue.