Large file uploads in ASP.NET
Uploading files via the FileUpload
control gets tricky with big files. The default maximum filesize is 4MB
- this is done to prevent denial of service attacks in which an
attacker submitted one or more huge files which overwhelmed server
resources. If a user uploads a file larger than 4MB, they'll get an
error message: "Maximum request length exceeded."
Server Error in '/' Application.
------------------------------
Maximum request length exceeded.
Solution:
The 4MB default is set in machine.config, but you can override it in you
web.config. For instance, to expand the upload limit to 20MB, add below code to web.config:
<system.web>
<httpRuntime executionTimeout="240" maxRequestLength="20480" />
</system.web>
IIS7(and later version) has a built-in request scanning which imposes an upload file cap which defaults to 30MB. To increase it, you also need to add the lines below:
<system.webServer>
<security>
<requestFiltering>
<requestLimits maxAllowedContentLength="3000000000" />
</requestFiltering>
</security>
</system.webServer>
Note: maxAllowedContentLength is measured in bytes while maxRequestLength is measured in kilobytes.
Warning: If you are using our shared hosting plan, we do not recommend you to upload large files via script which will slow down your site loading speed. You can upload it via FTP instead.
Article ID: 1544, Created: January 6, 2014 at 11:09 PM, Modified: January 6, 2014 at 11:51 PM