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Entry type: FAQ Entry ID: 11965771, Entry date: 01/28/2010

Where can I find explanations of the error messages of the WinCC diagnostics files License.log, WinCC_SStart_xx.log and WinCC_Sys_xx.log ?

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An explanation of the entries in the License.log are in the WinCC Information System under the item "Diagnostics in authorization problems".  The License.log shows the authorizations called. If WinCC switches to demo mode, for example, then you can see in the License.log for which missing license the demo has been started.

 Fig. 1: License.log

Here you find a log of all the events that have occurred since startup of WinCC in Runtime.

In this log file is a log of events that have occurred during the runtime of WinCC.  

Below is a selection of the system message windows generated most frequently by WinCC and entered in the log files WinCC_SStart_xx.log and WinCC_Sys_xx.log.



Text in Diagnostics



ActionOverflow: more than 5000 Actions to work

Overload, more than 5000 actions in the queue.


ExecuteError in Action (function name)

An error has occurred during processing of an action. The action ID is also given. If this is a Global Script action, the connection to the action name can be set up via the GSC Runtime application window as long as Runtime is not restarted or a Global Script stored.


No connection to server (server name)

Connection to server aborted.
Remedy: restart the server.


Function (function name) unknown

Unknown function.


No P code

A Global Script action or a function does not contain any executable code (P code).

Remedy: compile action or function


Variable does not exist

The variable requested is not available.


Variable timeout

Variable request not answered within a specific period of time.


FindFirstFile INVALID_HANDLE_VALUE GetLastError()

In the case of multi-user projects, the directory ..\Siemens\WinCC\aplib with the name SCRIPTFCT is released.
If the directory cannot be accessed, this entry is issued and a second attempt is made.


InstallClient ok

Communications client/server set up.


InstallClient not ok

A client could not get into communication with the server.


Thread said good-bye

A job thread has closed unexpectedly.


10 errors occurs, no more errors will be reported

Error has occurred 10 times and will no longer be logged for reasons of performance.


APDMConnect-Thread said good-bye

The thread providing the connection between action controller, tag management and other applications has closed unexpectedly.

Table 1: List of most common WinCC system messages

These and more error messages you find in Help of diagnostic tools APDiag as of version 5.0 SP2. This help file is located in "...\Siemens\WinCC\uTools\APDiagDeu.chm". 
As of WinCC V6.0 you find this help file in "...Siemens\WinCC\Documents\German\APDiag.chm".

More information on evaluating error messages in log files is available in Entry ID 8385493 and Entry ID 2357302.


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