The common reason this happens is the anti-virus and/or firewall software that is being used on the computer/server where our connector is installed.
One particular aggressive anti-virus tool is Symantec Norton.
We have seen their SONAR utility actively remove the software from the service flagging it as malicious.
If you are installing Norton we would advise setting up an exception to exclude the entire Motivity Connector folder from being scanned.
There is a screen shot of Norton attached highlighting where you set up this exception
You get to this screen from Advanced -> Anti-Virus -> Settings
We would also advise setting up rule to allow traffic through firewall too.
Contact us for further information about this.