If any of the selected functional tests for this load scenario includes data templates, then you will need to select the associated data sets before you can run your load testset. To do so, select the load test set of interest by clicking on the checkbox to the left of load test set name and click Edit, then click on Test Case and Data Set Selection.
1- You will see the same screen where you selected the test case. Select each of the automated functional tests and choose the data sets related to each of them and click on Save. 
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2- In case you need to deselect or select all, you can click All or None icons:
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3- You can also select custom data sets by clicking on Custom icon:
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4- From the Custom screen, you can select Range to select from a Start Index to an End Index:
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5- You can also select Random to select randomly by setting a maximum Count:
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6- Once finished, click Apply. To use the same data set on all selected test cases, click Apply button next to None.
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| title | TipYou can select and delete data sets in batches and you can also select multiple data sets and save them together. |
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TipData sets selected by one user do carry over to other users in the same account similar to execution sets |