Hi, Bruce
Don't know why I didn't think of this earlier, but I was able to replicate the problem in an Example app by turning on Multi-tab support. In the Basic with Menu example (2) I have added a button to the menu that opens a memory form and has a single memory field for the mail box name with popup lookup. The lookup assigns the mail box number to a memory variable and saves it as a Session Value. So far, so good. With Multi-tab support turned off, the session value is still there in Validate All is called with the Save button. With multi-tab turned on, the session value is empty.. There are trace functions in both After Lookup and Validate All to show the results.
Thanks.
Using 8.61
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