Symptoms
After downloading Parallels Desktop update when trying to run the image you receive error: 'One or more files necessary to update the software are missing. Contact the Parallels support team for assistance.'- Numerous attempts to download the update lead to the same error message every time, there are no errors while it is downloading.
- Your network connection goes through the router, e.g. NetGear WGR614 Wireless Router (http://en.wikipedia.org/wiki/Netgear)
Resolution
To resolve the issue, please follow the the steps below:1. Download the image file once again and place it to your Mac OS X Desktop.
2. Open Finder > Applications > Utilities > Terminal.
3. Type in Terminal (press Enter after each command):
cd Desktop
md5 ParallelsDesktop-parallels-en_US-5.0.9220.531002.dmg
Please note that the file name in the command should be equal to the real .dmg name that you have downloaded, this command is just an example.
4. Terminal will display you md5 sum of the file (http://en.wikipedia.org/wiki/Checksum), it will be 97139e286f44e3cef3f63e30185eaabb in our example.
5. If it differs, then on your router configuration page under WAN settings disable SPI (Stateful Packet Inspection) firewall and restart the router (http://en.wikipedia.org/wiki/Stateful_firewall).