How can I pause a SQLCE Query until the Table it is querying is no longer being accessed elsewhere?

Question

I have a method that queries a table for the count of its records. QA has discovered an "edge case" where if a particular operation is canceled in a particular order and speed (as fast as possible), the GUI "forgets" about the rest of the records in that table (the contents of the tables are uploaded to a server; when each one finishes, the corresponding table is deleted).

To be clear, this table that is having records deleted from it and then queried for count ("workTables") is a table of table names, that are deleted after they are processed.

What I have determined (I'm pretty sure) is that this anomaly occurs when a record from the "workTables" table is in the process of being deleted when the workTables table is queried for the count of its records. This causes an exception, which causes the method to return -1, which in our case indicates we should cuase the GUI to not display those records.

Is there a way to check if a table is in the process of having a record deleted from it, and wait until after that operation has completed, before proceeding with the query, so that it won't throw an exception?

For those interested in the specifics, this method is the one that, under those peculiar circumstances, throws an exception:

public int isValidTable(string tableName)
{
    int validTable = -1; 
    string tblQuery = "SELECT COUNT(*) FROM ";
    tblQuery += tableName;
    openConnectionIfPossibleAndNecessary();
    try
    {
        SqlCeCommand cmd = objCon.CreateCommand();
        cmd.CommandText = tblQuery;
        object objcnt = cmd.ExecuteScalar();
        validTable = Int32.Parse(objcnt.ToString());
    }
    catch (Exception ex)
    {
        validTable = -1;
    }
    return validTable;
}

...and this is the method that deletes a record from the "workTables" table after the corresponding table has had its contents uploaded:

private void DropTablesAndDeleteFromTables(string recordType, string fileName)
{
    try
    {
        WorkFiles wrkFile = new WorkFiles();

        int tableOK = 0;

        DataSet workfiles;
        tableOK = wrkFile.isValidWorkTable(); // -1 == "has no records"

        if (tableOK > 0) //Table has at least one record
        {
            workfiles = wrkFile.getAllRecords();

            //Go thru dataset and find filename to clean up after
            foreach (DataRow row in workfiles.Tables[0].Rows)
            {
                . . .
                dynSQL = string.Format("DELETE FROM workTables WHERE filetype = '{0}' and Name = '{1}'", tmpType, tmpStr);
                dbconn = DBConnection.GetInstance();
                dbconn.DBCommand(dynSQL, false);

                populateListBoxWithWorkTableData();
                return;
            } // foreach (DataRow row in workfiles.Tables[0].Rows)
        } 
    }
    catch (Exception ex)
    {
        SSCS.ExceptionHandler(ex, "frmCentral.DropTablesAndDeleteFromTables");
    }
} 

// method called by DropTablesAndDeleteFromTables() above
public int isValidWorkTable() //reverted to old way to accommodate old version of DBConnection
{
    // Pass the buck
    return dbconn.isValidTable("workTables");
}

I know this code is very funky and klunky and kludgy; refactoring it to make more sense and be more easily understood is a long and ongoing process.

UPDATE

I'm not able to test this code:

lock (this)
{
  // drop the table
}

...yet, because the handheld is no longer allowing me to copy files to it (I get, "Cannot copy [filename.[dll,exe] The device has either stopped responding or has been disconnected" (it is connected, as shown by ActiveStync))

If that doesn't work, I might have to try this:

// global var
bool InDropTablesMethod;

// before querying that database from elsewhere:
while (InDropTablesMethod)
{
  Pause(500);
}

UPDATE 2

I've finally been able to test my lock code (copies of binaries were present in memory, not allowing me to overwrite them; the StartUp folder had a *.lnk to the .exe, so every time I started the handheld, it tried to run the buggy versions of the .exe), but it doesn't work - I still get the same conflict/contention.

UPDATE 3

What seems to work, as kludgy as it may be, is:

public class CCRUtils
{
    public static bool InDropTablesMethod;
    . . .

if (CCRUtils.InDropTablesMethod) return;
CCRUtils.InDropTablesMethod = true;
    . . . // do it all; can you believe somebody from El Cerrito has never heard of CCR?
CCRUtils.InDropTableMethod = false;

UPDATE 4

Wrote too soon - the bug is back. I added this MessageBox.Show(), and do indeed see the text "proof of code re-entrancy" at run-time.

while (HHSUtils.InDropTablesMethod)
{
    MessageBox.Show("proof of code re-entrancy");
    i++;
    if (i > 1000000) return; 
}
try
{
    HHSUtils.InDropTablesMethod = true;
    . . .               
}
HHSUtils.InDropTablesMethod = false;

...so my guess that code re-entrancy may be a problem is correct...