To properly log values, the AMPscript variable names must match the field names in the Send Log (A).

Additionally, Send Logging must be configured and enabled during the send setup to ensure data is captured into the log (C).

Simply linking a Send Log to an Attribute Group (B) is irrelevant to Send Logging. WriteToLog() (D) is used mainly for server-side debug logging, not for populating Send Logs.

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Exact Extracts from Salesforce Documentation:

Source: Salesforce Help – Send Logging Overview

→ "To log values to the Send Log, AMPscript variable names must exactly match the corresponding field names in the log, and logging must be enabled during the send process."

Source: Salesforce Help – AMPscript Functions (WriteToLog)

→ "WriteToLog() is primarily used for troubleshooting and development, not for writing data to the Send Log."

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