Got error "File exceeds the 30720KB limit" when preview file on web portal

When preview a document on web portal, including viewing files in My Files, or previewing file in shared file/folder, user may hit the error "File exceeds the 30720KB limit"

The file preview is generated on the Centrestack server. It uses server resources, especially when generating the file preview for large files. Thus Centrestack puts a 30M limit here. The error user got means the file is too big for file preview. Please download the file to local and open it from there.

The Centrestack administrator can change the limit on root\web.config.

• On Centrestack server, go to Centrestack installation folder\root.
• Make a backup of web.config
• Edit web.config
• Add the following setting in the file, within AppSettings section.
  <add key="MaxAllowedDocViewLimit" value="52428800" />
• Save the change.
• Open IIS Manager. Go to Application Pools. Recycle namespace application pool

It will change the size limit from default 30M to 50M. 

However, the file preview is generated on Centrestack server. After the change, please monitor the server performance. If you see performance is affected, delete the line to change it back to default value.