How to solve the upload image log problem to change alfresco's icon in admistrator panel page?

[savita]

I want to change de Alfresco's icon but there is an error to upload other image. 

When I try to upload the image to change the icon it presents this error:
 2017-09-18 19:30:45,218 ERROR [repo.jscript.ScriptNode] [http-bio-8080-exec-7] 08180025 Unsupported transformation: transformer.ImageMagick image/png to image/png
 2017-09-18 19:35:51,729 ERROR [repo.jscript.ScriptNode] [http-bio-8080-exec-16] 08180026 Unsupported transformation: transformer.ImageMagick image/png to image/png

[douglascrp]

Do you have ImageMagick installed and configured correctly?

One idea to validate it that is true is to upload a document and check if the thumbnail is correctly generated.