HowTo - Handle '413. Request Entity Too Large' error in installations with SSL/HTTPS setup

HowTo - Handle '413. Request Entity Too Large' error in installations with SSL/HTTPS setup

This error may occur in certain installations with SSL / HTTPS setup, in cases when clients send significant amount of data to server, more than the default limit of 49'152 bytes in IIS.

That is because the entire request entity body must be preloaded during negotiation and, additionally, SSL will use the value of the UploadReadAheadSize metabase property to validate the request size.

Solution

UploadReadAheadSize value of IIS must be increased to a higher limit (we recommend ~4Mb). You can run the following command with ADMIN rights:

C:\Windows\System32\inetsrv\appcmd.exe set config "Default Web Site/BACore" -section:system.webServer/serverRuntime /uploadReadAheadSize:"4915200"  /commit:apphost

IIS screenshot to verify if the value is increased: