This sounds really as a Windows 2008 problem.
I had the same problem and it occurs when you have the network interface card in Windows 2008 set to auto.
Try setting the nic to 100MB's full duplex or half duplex. That solved my problem.

Thanks. I try this but it was no solving the problem

The problem is over wan connections.

And for information, the version of 2008 server is Windows Web Server 2008

Hi,

Please you can always reach support using the below contact information:

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Regards,
Bala

Have you try to change C:\Program Files\Altiris\StreamingAgent\bin\AppstreamCfg.txt file:

PROXY_CACHE_OFFLINE_BANDWIDTH_LIMIT=0

0 means no bandwith limit

You should take into account the location(s) of your streaming server(s), endpoints, and if applicable, proxy server(s). As for "appstreamcfg.txt", make sure to take into account "PROXY_CACHE_MAX_BLOCKS_PER_REQUEST=", which by default is set to "0". Which is a no max request for blocks. See my SWS primer (https://www-secure.symantec.com/connect/articles/w...), I talk about proxy caching and how to configure it.

Given the network conditions and location of the proxy server (if there is one), this could contribute to streaming performance issues. A very likely first place to look would be your WAN. The reason for this is that with a no limit block request or any large traffic you will likely hit your CIR and get throttled very quickly, which would in effect choke your streaming. Imagine sending 10,000 cars onto a 2 lane highway. Raise your hand if you're calling in sick that day. Speaking of network traffic, if you have some type of QoS implemented, make sure that your streaming traffic is given some lanes to drive down. If your bandwidth issues are at your endpoints, try to change NICs from auto-detect to the line speed. You can also try changing the max offline streaming bytes/second. Logon to your console which is on http://BackEndHostName:9842, click Server Group under Configuration --> Configure --> Advanced tab, and increase "Maximum Offline Streaming:". Scroll down and click "Save" and restart components as directed, which can be done under the Component Status screen. Once status is all green (F5 or set refresh frequency) try streaming again.

The best thing to do to isolate this, or at least give yourself a direction to look in, is to drop a large file (500mb or more) on the streaming server, which is your front-end in a multi-node setup. Create a share on the same drive you installed on and place the file there. Open this share from your endpoint then try a simple file copy. This will help identify if the issue is with streaming or the network. You can also run this test during low usage and peak usage hours of the day to compare. Keep in mind however, when you are streaming, this can and will be impacted by the health of the endpoint. Registry and file fragmantation can add a good deal of latency, so even if you could have unlimited bandwitch, you would still be at the mercy of what your endpoint can handle. You can have one endpoint streaming quickly and another taking it's sweet time on the same LAN, regardless of bandwidth.