Web query returned no data!

I've been using following code to retrieve data from the web. It worked fine yesterday, but it will not work today or on another workstation. The connection was first added, and then the code was changed to the following in order to keep from continually adding new connections:

HTML Code:

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    With ActiveSheet.Range("A1").QueryTable
        .Connection = _
        "URL;" & url

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Now I get this error: "This web query returned no data. To change the query, click OK, click arrow on the name box in the formula bar, click the name of the external data range for the Web query, right-click the selection, and then click Edit Query".

If I change the code to add a new connection, data is retrieved successfully :

HTML Code:

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  With ActiveSheet.QueryTables.Add(Connection:= _
        "URL;" & url _
        ', Destination:=Range("$A$1")

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If I leave the above code, however, it keeps adding new connections to the workbook. I don't understand query connections yet and would appreciate your help. How can I set up and use the same connection? Thanks.