There are a lot of reasons that would cause a store connection to fail - Here is where I would start:
1) Is the connection schedule defined in HQ Mgr?: HQ Mgr> Admin> Stores> Locate/Highlight store> Properties> Connection Schedule - is schedule according to your connection map?
2) Make sure stores connections are staggered (not one store connects at the exact same time, even if on different ports)
3) Is HQ Client installed? If you have recently reinstalled RMS, make sure you have reinstalled HQ Client
4) HQ Client HQ Server info is incorrect (try test Network Connection) from HQ Client> File > Config> HQ Server> verify connection port and IP are accurate> Test Network Connection
5) At the same time, make sure the port you run this store on is up and active on your RMS Server
6) Does the store have any errored WS 401's? From HQ Mgr> View> WS Status> if you display by WS, click 401> Check for any errors
7) Acknowledge any WS401 errors by: HQ Mgr> Admin> Worksheet> Enter errored WS#> Properties> Acknowledge
8) Check Log Files for errors against store: HQ Mgr> View> Event Log> Select Store> Scroll through looking for error codes or things that look off> Note> Research
9) Recreate and issue WS401's Issue a 401 against store> Call> Request store process (HQ Client> Server> Connect)> watch connection come through on HQ Mgr Event Viewer - looking for errors.
When was the last successful connection you had with this store? What version of RMS are you running? Did you see any errors in the event viewer, if so, what?