Attachment field size considerations
When setting the Max Size property for an attachment field, set a size that is large enough to accommodate typical attachments but small enough to conserve database space. If the size of an attachment exceeds the attachment field's allocated space, users cannot add an attachment to it even when the attachment pool contains other empty attachment fields.
Attachment size can also be limited by the available memory on the client computer. For example, your database might allow attachments up to 2 GB but be limited to attachments of only a few MB because of client memory constraints.
To set maximum attachment sizes for Oracle (including memory allocation), Microsoft SQL Server, and Sybase databases, see Db-Max-Text-Size.
Remote procedure call (RPC) and memory allocation errors might occur when users open large attachments on computers with limited memory resources. The error that appears depends on the stage of transfer (from client to server computer) at which the memory failure occurred. If you receive a "malloc in client library failed" error, check the memory resources of the client. If the error is "Unable to send," check the memory resources of the client and server. If it was a database-specific memory error, check the data or log (or transaction) space.