Issue:
The Update Signature portion of the pre-defined schedule task VMWare Update Manager Update Download is queued.
Cause:
The cause is usually one of the following
1) Web filtering software is blocking access to the VMWare Update Manager sites or requiring user login
2) The Proxy server settings for the scheduled task are incorrect.
3) The scheduled task has become corrupted and needs to be recreated
4) Incorrect Firewall configuration
Solution:
Web Filtering Software
Some web filtering software relies on integrated authentication or manual user login (without using a proxy configuration) to gain access to the internet. In this case you may need to make adjustments to policies to allow the VirtualCenter (VC) server access to the required sites (www.vmware.com and www.shavlik.com), or all of the Internet without requiring user authentication.
Simple tests can verify that user authentication via web filtering is the issue. For example, have an administrator login locally to the VC server and access the Internet. Then run the scheduled task manually. If the task works correctly, it is most likely user authentication via web filtering software causing the issue. You can also use the Test Connection button on the Internet Access settings page to test your web filtering software. See screenshot in Proxy Server Settings section for more information.
On rare occasions the update repository sites (www.vmware.com and www.shavlik.com) may be blocked via web filtering software. In this case modify the policy or site restriction as needed to allow access.
Proxy Server Settings
If you are using a proxy to access the Internet you will need to configure the VMWare Update Manager Update Download task with the appropriate proxy server settings. See screenshot below on where to configure these settings. The update manager plug-in is required to access these settings.
Recreate the scheduled task
To recreate the scheduled task do the following
1) Delete the existing scheduled task from the Scheduled Tasks list.
2) Create the schedule task using the Edit Update Downloads link in the Update Manager plug-in. See the screenshot below for more information.
a. The Update Manager plug-in is required to access these settings.
Incorrect Firewall Configuration
To obtain metadata and download the updates the Update Manager service must be able to connect to www.vmware.com and www.shavlik.com via outbound ports 80 and 443.
More Information:
You can stop and restart the VirtualCenter Server service to clear any queued (hung) scheduled tasks.
VMware Update Manager Network Port Requirements