Follow below points
1. Connect to your Report Server from SSMS.
2. Note the ItemID for your report by executing this query
select *
from ReportServer..Catalog
where Path like '%NameofyourReport%'
3. Create a job in here with the name say "AppendDatetoxyzreport" and add a step in it with the code
UPDATE [Catalog]
SET [Path] = '/PathofyourrerportfromReportServer/ReportName_' + CONVERT(VARCHAR(8), GETDATE(), 112),
[Name] = '/ReportName_' + CONVERT(VARCHAR(8), GETDATE(), 112)
WHERE ItemID ='<itemid>'</itemid>
4. Create another job with a name like "RemoveDatexyzreport" and add a step in it with the code
UPDATE [Catalog]
SET [Path] = 'PathofyoureportinReportserver/ReportName',
[Name] = 'ReportName''
WHERE ItemID = '<itemid>'
</itemid>
5. Now set your AppendDatetoxyzreport job schedule to execute first, then the Report's subscription and then the RemoveDatexyzreport.
Source:
http://social.msdn.microsoft.com/Forums/sqlserver/en-US/ddfd922b-613a-49f3-b403-b70cd66a8127/append-date-to-exporting-file-name-in-sql-reporting-service[
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