In Exchange 2013 i cannot open mails with attachments greater than 19.6 MB in EWS or OWA

Question

Hello,
i have in Exchange 2013 CU3 on Windows 2012 the following problem :
When backup mails using EWS i get the message " EWS Error Code : ErrorMessageSizeExceeded." in mails with attachments greater than 20.137 KB ( 19.6 MB).
Then I checked all the settings of the EWS , but the defaults are already significantly higher than these 19.6 MB (Base64 approximately 26.5 MB)
web.config ( maxAllowedContentLength = " 85000000 ").
Settings of the MaxSendSize and ReceiveSize are 300MB .
All requestfiltering settings in IIS are set to 85MB.
When i access via EMS or OWA , file attachments over 19.6 MB can not be opened .
However, the preview shows in OWA the correct mail including attachment and it can be saved from the preview up to the set maximum size.
By double clicking on an email in OWA bigger than 19.6 MB i get the following error message:
"Error : Your request can not be completed right now Please try again later . . "
Send and receive mail can also be up to maxsize .
When accessing via Outlook , this problem does not occur.
i hope anyone here can help me
Thanks in advance

Answer 1

Hi,
To change the maximum message size for Outlook Web App clients, you need to change the value of
maxAllowedContentLength, maxRequestLength and both instances of
maxReceivedMessageSize by editing %ExchangeInstallPath%ClientAccess\Owa\web.config in notepad.
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%ClientAccess\exchweb\ews\web.config.
When you are finished, save and close the Web.config file. Also need to restart IIS by running the following command:
IISReset /noforce
For more information about Configure Client-Specific Message Size Limits on Client Access Servers, please refer to:
http://technet.microsoft.com/en-us/library/hh529949(v=exchg.150).aspx
Thanks,
Winnie Liang
TechNet Community Support