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Full Circle Insights

Matchmaker KB 1009: Error Message: "Your Salesforce matching rule wasn't activated - one or more match keys resulted in more than 100 duplicate records"


When attempting to activate the Matchmaker matching rule, you may receive an error email from Salesforce stating that the activation was unsuccessful.  The error email looks something like this:

Hello Full Circle,

You tried to activate the matching rule Lead to Account for identifying duplicate records. We can't activate Lead to Account, because it generated one or more match keys that resulted in more than 100 duplicate records.

Problem match keys:

Change Lead to Account to narrow the number of records with identical match key values, and then try activating the rule again.

For more information, search for “Match Keys Used with Matching Rules” in Salesforce Help.

Matchmaker utilizes Salesforce duplicate management functionality to support matching.  In Salesforce there is a concept of Match Keys Used with Matching Rules:

A match key is a formula that allows a matching rule to quickly return a list of possible duplicates.  In orgs where there are 

  • 100+ accounts with the same website or 
  • 100+ accounts with similar names, i.e. the first 6 characters of the first two words of the Account Name

Salesforce fails to create match keys and fails to complete activation of a Matching Rule because there are too many duplicate records found. Matchmaker uses a matching rule and we can't get it to activate because of the condition of the data. 

Starting with the Summer '17 release, a new feature was enabled whereby Salesforce blocks activation of an "ineffective matching rule" and sends an email with more details to the admin who tried to activate it.  Please reference the Salesforce documentation here: and


Until the matching rule can successfully be activated, Matchmaker will be unable to function in the org.

Solution: Clean Your Data

This error presents itself in orgs where there is a lot of test data or where data cleansing and normalization has not been practiced.  You'll need to run reports on your account data and determine what account records are being treated as similar.

Some guidelines:

  • If you received a match key error on the account field Website, review whether you have many accounts with a generic website like "" or "http://na"? If so, these values will need to be cleared.
  • If you received a match key error on the account field Account Name, do you have several accounts that are marked with a certain prefix? A common scenario that may cause problems would be several hundred accounts that begin with a two-word state name, such as "New York", or university accounts that begin with "University of".

If you're unable to optimize the data, another potential solution is to include additional criteria in the matching rule, such as Zip or City. This is not the initial recommended solution because it is preferable to use Matchmaker's Match Prioritization Rules to narrow down the potential account matches instead of relying on the Salesforce Duplicate Management process.