Hi JOYSON,
The default upload file size is 4MB. Please set maxRequestLength as per your requirement (in KB).
<configuration>
<system.web>
<httpRuntime maxRequestLength="1048576" />
</system.web>
</configuration>
For IIS7 and above you also need to add the lines below.
<system.webServer>
<security>
<requestFiltering>
<requestLimits maxAllowedContentLength="1073741824" />
</requestFiltering>
</security>
</system.webServer>
Note: maxAllowedContentLength is measured in bytes while maxRequestLength is measured in kilobytes, which is different in this config example. (Both are equivalent to 1 GB)
If you want to handle the error please refer the below link.
https://stackoverflow.com/questions/665453/catching-maximum-request-length-exceeded
