You can easily change the date on a batch prior to posting. From your CMS Contribution System, click Enter Contributions. From the Select Batch screen, just click into the erroneous date and change it to the correct date.
If you've already posted the batch of contributions, there are just a few more steps involved.
Make sure you have a backup of your data before beginning this process.
You will need to know the Batch Number, the date that was used, and the date that should have been used when posting.
From CMS, click File | Utilities | CMS File Editor | click OK at the warning message.
Click the Select Table to Edit button and open the DETAIL.DB table.
You will see a screen with several columns and rows of data. One of the columns is Batch Num. Right-click the first number you see under the Batch Num column (not the words Batch Num, but the actual number) and choose the word Filter.
At the Filter for Batch Num field, type in the batch number with the wrong date. Click OK.
Now the only batch number you should see is that batch number, probably repeated in many rows.
Click the Edit button at the top of the screen.
Single left click into the Date column (the date, not the column header "Date").
Click the Locate and Replace button at the top of the screen.
Verify the Field = Date.
Click into Value and type the incorrect date. Make sure to use the format mm/dd/yy when entering the date, as it will not "auto format" for you.
Click into the Replace With field and type in the correct date. Again, make sure to use the mm/dd/yy date format.
At the "Found a Match" display, choose the last option of Change All Occurrences and click OK.
The system will find all of the incorrect dates and replace them with the corrected dates. The system will not give you a notice when complete, it will just stop. Click Close.
If you changed a date within your current quarter, you're done!
If you changed a date from a prior quarter, click File | Utilities | Repost Utility | Process.
This will recalculate all of your QTD, YTD, and Calendar YTD totals, based on the new information. Once complete, go back into the Contribution System.
Click Process | Calculate Pledge Balances | Process. This will recalculate any Drive to Date and pledge balance totals.
Once that's complete, you're done!