When I uplode the file

Uncaught SyntaxError: Unexpected token < in JSON at position 761at JSON.parse (<anonymous>)at Function.parseJSON (jquery.min.js:4)at Gdn_MultiFileUpload.Gdn_MultiFileUpload.UploadComplete (fileupload.js:448)at Gdn_MultiFileUpload.<anonymous> (fileupload.js:308)at HTMLIFrameElement.i (jquery.min.js:4)at HTMLIFrameElement.dispatch (jquery.min.js:5)at HTMLIFrameElement.v.handle (jquery.min.js:5)parseJSON @ jquery.min.js:4Gdn_MultiFileUpload.Gdn_MultiFileUpload.UploadComplete @ fileupload.js:448(anonymous) @ fileupload.js:308i @ jquery.min.js:4dispatch @ jquery.min.js:5v.handle @ jquery.min.js:5

{"MediaResponse":{"Status":"success","MediaID":"2485","Filename":"2017-03-24 20_25_34-\u767e\u5ea6\u4e0b\u9762\u6709\u8fd9\u4e48\u4e00\u6bb5\u4ee3\u7801\uff0c\u5982\u4f55\u7834\uff1f\u4f1a\u5bfc\u81f4MutationObserver(chrome)\u51fa\u95ee\u9898 - Greasy Forum.. - Cent Browser.png","Filesize":67404,"FormatFilesize":"65.8K","ProgressKey":"","Thumbnail":"PGltZyBzcmM9Imh0dHBzOi8vZ3JlYXN5Zm9yay5vcmcvemgtQ04vZm9ydW0vdXRpbGl0eS90aHVtYm5haWwvMjQ4NS9GaWxlVXBsb2FkL2RjL2FmZTEzMTA5MmVhZmM1NTI5ZTc0MGM3NmE0YjZlZS5wbmciIGNsYXNzPSJJbWFnZVRodW1ibmFpbCIgLz4=","FinalImageLocation":"https:\/\/greasyfork.org\/zh-CN\/forum\/uploads\/FileUpload\/dc\/afe131092eafc5529e740c76a4b6ee.png","Parsed":{"Name":"FileUpload\/dc\/afe131092eafc5529e740c76a4b6ee.png","Type":"","SaveName":"FileUpload\/dc\/afe131092eafc5529e740c76a4b6ee.png","SaveFormat":"%s","Url":"https:\/\/greasyfork.org\/zh-CN\/forum\/uploads\/FileUpload\/dc\/afe131092eafc5529e740c76a4b6ee.png"}}}