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System Tags in KEPServerEX represent server, channel, and device-level properties. These tags are pre-defined by the server, and the tag name is prefixed with an underscore. Some of these tags are read only, but some may be written to by a connected client. When writing to System Tags, there may be special settings to be considered in KEPServerEX. Both the location of the System Tag settings and the default access for read/write permissions depends on the version of KEPServerEX being used. For more information, refer below.

Disabling System Tag Writes in Server Version 4.x

1. In the server menu, click Tools | Options.
2. Next, open the OPC Settings tab.
3. To disable writes, uncheck Allow Client to write to system tags.

Enabling System Tag Writes in Server Versions 5.0 to 5.7

1. Right-click on the Administration Utility and then select Settings.
2. Next, open the Runtime Options tab.
3. To enable writes, check Allow clients to write to system-level tags.

Enabling System Tag Writes in Server Versions 5.8 and After

1. Right-click on the Administration Utility and then select Settings.
2. Next, open the User Manager tab. Then, double-click on the Data Client user (or the Anonymous Clients user group for version 5.12 and higher).
3. To enable writes to all tags, check Allow writes to system tags.