Users cannot sign in to the CrashPlan console because a content filtering application is being used to monitor user access to the Internet. This article describes the problem and how to resolve it.
CrashPlan for Small Business users attempt to sign in to the CrashPlan console, but are unable to connect. The errors returned in this situation may vary, though HTTP response codes 400 and 431 are most likely.
Content filtering is a common practice to ensure employees do not access restricted Internet content. In most cases, the filter only is set to prevent access to certain areas of the Internet that are restricted by your company's policies. However, if your company's content filtering software uses a web proxy, it can interfere with the ability of users to sign in to the CrashPlan console.
If you suspect that content filtering may be the cause, add the CrashPlan console address to your content filtering software's allowlist. Doing so will ensure that users can access the CrashPlan console without interference from your company's content filtering software.