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I'm using Huawei HG556a with a Huawei E173 USB HSPA Modem. I have been using it fine but recenly after I reset the router, it desn't seem to connect to the internet using USB Modem automatically. Everytime I shut down the PC, it disconnects and I need to reconnect it either by turning on the computer or using my phone after going in to routers page. This never happend before. It used connect to the internet automatically and stay that way until I tun off the router. Any ideas about what's going on?
Thanks for posting.
The first thing I'd check is software updates for your modem. You can get the latest version here.
If this doesn't help can you try uninstalling the modem software from your computer and installing it fresh.
Let me know the outcome.