In Microsoft CRM 2011, the file size limit can be increased through the CRM interface from 5MB (5,120 KB) to a maximum of 32MB (32,768 KB), whereas in CRM 4.0 file size changes were done through an unsupported manner via the web.config file which required an IIS restart.
The default attachment file size limit in Microsoft Dynamic CRM 2011 is 5MB. As files attached to CRM are stored in the database, restrictions should be placed on the amount of file data that can enter CRM so that the database can maintain a reasonable size and so that performance is optimized.
However, business changes may find the need to increase this size in order to handle larger file attachments. While files to the size limit of 32MB can be attached, the infrastructure of the CRM application needs to be considered so that performance is not impacted.
Here are the instructions to increase the file size limit to 10MB (10,240 KB):