The attachment could not be opened
PROBLEM:
Encountering the following errors:
- The attachment could not be opened
- The remote server returned an error: (507) insufficient storage
SOLUTION:
The reason is probably the size of the attachment. EWS is limiting access to large attachments, but this limit can be extended.
In order to change the limit, edit the EWS configuration file on all CAS servers:
To change the maximum message size for Exchange Web Services clients, you need to change the value of maxAllowedContentLength and all instances of maxReceivedMessageSize="67108864″ in %ExchangeInstallPath%ClientAccessexchwebewsweb.config
Also the update to Exchange 2013 SP1 should resolve the problem.