In CONNECT Edition Update 1, when laying out new conduits, the labels of the conduits increment by two. In other words, numbers are skipped and the order may be something like CO-2, CO-4, CO-6 for example.
This is a known issue in CONNECT Edition Update 1 (10.01.00.70), which has been fixed in the latest cumulative patch set (Defect #809868). To fix the issue, contact technical support for the latest cumulative patch set, or upgrade to a newer version when available.
Note that the Tools > Options > Labeling dialog cannot be used as a workaround. For example if you change the "increment" for conduits, that increment will be multiplied by two, and the increment cannot be set to 0.5.
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