As a best practice, first stop all the services, restart your servers (where the services are are installed) on a daily basis and re-start all the services.
Make sure all the services are running fine in the Status>>Services tab of QMC.
Check for the access to the credentials used while installing the services. Are those approved or do they have licenses?
"services are running fine in the Status>>Services tab of QMC' - after QV Management Servce restart the only one not working was reload enginee, other [DSC,QVS,QVWS] were running ok.
QV Server and Desktop were isntalling by user with Admin and QV Admin credentials.
i'm not sure if restart on a daily basis is good solution
First, check that the version of IE is compatible with QMC, (for version 10, if I remember correctly, it's IE 7 and higher). Second, make sure that there is no proxy set up in the QlikView Server, and if there is, add the QlikView server to its exceptions, as the QMC retrieves information and status from the other QlikView services by different ports that may be closed in your proxy or firewall.
Finally, make sure the account running the QlikView services is part of the local Administrators group, and that the password of the account has not been changed.
Hope that helps.