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Software Installation Failure

Failure to Connect to the Central Repository Server (CRS)


You cannot connect to the central repository when you are trying to synchronize application details. The error message that you see on the screen is, 'Failed to connect to the central repository'.


You cannot connect to the central repository when you are trying to synchronize application details because you:

  • Have not defined proxy settings, or the existing proxy settings are invalid or have been changed
  • Have not added "sync.patchquest.com" and "patchdb.manageengine.com" to the exception list of your proxy server
  • Do not have access rights to the vendors' Web sites

You may also face this problem when the proxy server does not allow communication through ports 80 and 443.


You are required to identify why you cannot connect to the central repository, when you are trying to synchronize application details. Follow one of the solutions given below, depending on what the problem is. 

Defining valid proxy credentials

You are required to define the proxy settings.

Note: If you have already defined the proxy settings, check them for validity.

To define valid proxy settings, follow the steps given below:

  1. Click the Software Deployment tab > Proxy Settings
  2. Enter the following details:
    • HTTP proxy host
    • HTTP proxy port
    • User name
    • Password
  3. Click OK

The Desktop Central server will validate the proxy credentials.

Providing access rights

The administrator must provide:

  • Specify proxy credentials of users who have download rights
  • Access rights to the systems, to download application-specific details from "sync.patchquest.com" and "patchdb.manageengine.com".

Configure Proxy Server Settings

You are required to do the following tasks:

  • Open ports 80 and 443 to allow the proxy server to communicate
  • Add the sync.patchquest.com to the exception list of your proxy server

Applies to: Software Installation, Software Installation failure, Software Deployment Status, Failure to Connect to the CRS

Keywords: Software Installation Failure, Deploy Software, Install Software on Remote desktops, Software Installation Error

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