You have put the try-catch block in the wrong place!

ALTER TABLE (TT) ADD COLUMN TXPNO C(19) 
ALTER TABLE (TT) ADD COLUMN YEARe C(6) 
ALTER TABLE (TT) ADD COLUMN INFTYPE C(2) 
ALTER TABLE (TT) ADD COLUMN INFDATE C(12) 
ALTER TABLE (TT) ADD COLUMN OFFCODE C(6) 
ALTER TABLE (TT) ADD COLUMN ENTRYID C(15) 
ALTER TABLE (TT) ADD COLUMN ENTDATE C(12) 
ALTER TABLE (TT) ADD COLUMN CONFFLAG C(3) 
ALTER TABLE (TT) ADD COLUMN CONFID C(12) 
ALTER TABLE (TT) ADD COLUMN CONFDATE C(12) 
replace TXPNO WITH THISFORM.TEXT1.Value
replace YEARe WITH THISFORM.TEXT2.Value
replace INFTYPE WITH THISFORM.TEXT3.Value
replace INFDATE WITH THISFORM.TEXT4.Value
replace OFFCODE WITH THISFORM.TEXT5.Value
replace ENTRYID WITH THISFORM.TEXT6.Value
replace ENTDATE WITH THISFORM.TEXT7.Value
replace CONFFLAG WITH THISFORM.TEXT8.Value
replace CONFID WITH THISFORM.TEXT9.Value
replace CONFDATE WITH THISFORM.TEXT10.Value


FOR gnCount = 1 TO FCOUNT( )
   m.OldName =  FIELD(gnCount)
   m.NewName = ALLTRIM(EVALUATE(FIELD(gnCount)))
     *******************************************************
   Try
      ALTER TABLE (tt) RENAME COLUMN (m.OldName) TO (m.NewName)
   Catch
      Wait 'Oldname with error is '+m.oldname window
      Wait 'Newname with error is '+m.newname window
   Endtry
 NEXT

>i try as below, but i think it is wrong way becuse no result
>
>

>CLOSE all
>SET DATE BRITISH
>SET CENTURY on
>thisform.text11.Value=GETFILE('xls')
>IMPORT FROM (thisform.text11.value) TYPE xls
>
>use JUSTSTEM(thisform.text11.value)
>tt=JUSTSTEM(thisform.text11.value)
>
>CLOSE all
>USE (tt) excl
> Try
>*set step on
>ALTER TABLE (TT) ADD COLUMN TXPNO C(19)
>ALTER TABLE (TT) ADD COLUMN YEARe C(6)
>ALTER TABLE (TT) ADD COLUMN INFTYPE C(2)
>ALTER TABLE (TT) ADD COLUMN INFDATE C(12)
>ALTER TABLE (TT) ADD COLUMN OFFCODE C(6)
>ALTER TABLE (TT) ADD COLUMN ENTRYID C(15)
>ALTER TABLE (TT) ADD COLUMN ENTDATE C(12)
>ALTER TABLE (TT) ADD COLUMN CONFFLAG C(3)
>ALTER TABLE (TT) ADD COLUMN CONFID C(12)
>ALTER TABLE (TT) ADD COLUMN CONFDATE C(12)
>
>
>
>replace TXPNO WITH THISFORM.TEXT1.Value
>replace YEARe WITH THISFORM.TEXT2.Value
>replace INFTYPE WITH THISFORM.TEXT3.Value
>replace INFDATE WITH THISFORM.TEXT4.Value
>replace OFFCODE WITH THISFORM.TEXT5.Value
>replace ENTRYID WITH THISFORM.TEXT6.Value
>replace ENTDATE WITH THISFORM.TEXT7.Value
>replace CONFFLAG WITH THISFORM.TEXT8.Value
>replace CONFID WITH THISFORM.TEXT9.Value
>replace CONFDATE WITH THISFORM.TEXT10.Value
>Catch
>   Wait 'Oldname with error is '+m.oldname window
>   Wait 'Newname with error is '+m.newname window
>Endtry
>
>
>FOR gnCount = 1 TO FCOUNT( )
>   m.OldName =  FIELD(gnCount)
>   m.NewName = ALLTRIM(EVALUATE(FIELD(gnCount)))
>     *******************************************************
>   ALTER TABLE (tt) RENAME COLUMN (m.OldName) TO (m.NewName)
>
>NEXT
>
>

>
>
>>I'm pretty sure that your problem is the name of the fields, and not the syntax. Try something like this

>>Try
>>   Alter table...
>>Catch
>>   Wait 'Oldname with error is '+m.oldname window
>>   Wait 'Newname with error is '+m.newname window
>>Endtry

>>Then you write down the wrong values, and tell me what they are.
>>
>>>sorry i don't now what you main, or how i can know(to get) the value for OldName and NewName
>>>What is the value of OldName when you get this error?
>>>What is the value of NewName when you get this error?
>>>
>>>>Please answer my two simple questions!
>>>>
>>>>>if you main when i make replace via textboxes it's characters and numbers ,
>>>>>
>>>>>if you main excel sheet i have some fields have numbers ,and some fields have characters and ONE field have first record as blabla and next as #
>>>>>
>>>>>
>>>>>
>>>>>>What is the value of OldName when you get this error?
>>>>>>What is the value of NewName when you get this error?
>>>>>>