-104 ERR APP IN USE (Magic xpa 4.x)
This error message appears when one of the following occurs:
- 
The Broker Filter limit is exceeded (and the enterprise server is not completely busy).
 - 
The engines are blocked (for example by using the RqRtBlock() function). You can verify this by checking the status of the engine in the broker monitor.
 - 
The engines are busy.
 
If you encounter this error while all the engines are not blocked or busy, you should:
- 
Increase the value of the BrokerTimeout keyword in the Mgreq.ini file or the Timeout property in the broker's server properties when using remote calls.
 - 
Set the value of the RequesterTimeout keyword in the Mgreq.ini file to 0.