Resolving an 'onReadyState' error In CAESAR

The October 2017 update to CAESAR has resulted in incompatibility with Kaspersky Labs Antivirus. To resolve an 'onReadyState' error, shown in the screenshot below, you must pause the Kaspersky extension in your browser. Instructions on how to do this in various browsers can be found at .

Kaspersky error

The error message will include a web address from the kaspersky-labs domain, such as the following (emphasis added):

Function 'onReadyState' Error: Failed to execute 'querySelectorAll' on 'Element': '[src="" charset="UTF-8"] is not a valid selector. 

For additional assistance please contact the IT Support Center at 847-491-4357 (1-HELP) or via email at

Keywords:kaspersky labs antivirus   Doc ID:77582
Owner:IT Support Center .Group:Northwestern
Created:2017-10-24 14:55 CSTUpdated:2019-02-04 10:59 CST
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