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LV DSC: Error Accessing Historical Database

I have an SCF file that contains a couple tags. When I launch the tag engine, it launches the appropriate VI-Based Server and logs data.

The first time I launch the engine with this SCF file it works great. Data is logged to Citadel with no errors.

I then stop the engine and restart it (using the same SCF file). I then get this message when the VI-based server tries to write to Citadel:

ERROR 11/26/2001 03:06:00 Error Accessing Historical Database! Error Code: -1967390689 (0x8ABC001F)

This error message provides very little info for debugging purposes. Where can I track down what these error codes mean? No reference to this error on NI's support pages. Any ideas?
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The -1967390689 points to a problem attempting to log to a buffer that is full. There are couple of things that can be done to address the problem. First, you can try increasing the queue size in the Tag Configuration Editor (Configure>>Engine>>Server).Secondly,in the Logos.ini file (Win9x: c:\windows\system\logos.ini, WinNT/2k: c:\winnt\system32\logos.ini, look for

MaxQueueSize=### in points
LogPeriod=### in milliseconds

MaxQueueSize is the number of times a single point can change before DSC or Lookout finishes configuring all points for logging. The default is 500. Setting this to something like 5000 will probably give DSC enough time to configure points.

LogPeriod is how often the logging buffer is flushed to the datab
ase. The default is 200. If you have a lot of points, this can be very slow, since DSC needs to get the timestamp from each point before logging to the database. Setting this to something like 2000 (2 seconds) or more will free up the processor a bit, although HyperTrends will update considerably less often, but they are probably doing that anyway if the logging buffer is filled up.

Lastly, you may try upgrading to the newest release of Logos. The Logos 4.3 installer can be downloaded from

Message 2 of 2