Making It Happen
Accounting and Information Technology, Assistance and Support
Sage 50 - What to do if you have errors

Safety first.

1/ Get everyone out of Sage 50 and stop using it.
2/ Disconnect or close any 3rd party software integrating with Sage 50
3/ BACKUP Label this backup as having errors

Breathe

4/ Make a mid year archive of your data
          Tools>Period End>Archive Company
5/ Restore the last known good backup
          File>Restore
6/ Check the data is good
          File>Maintenance>Check Data
7/ If it is good, do Reindex and Compress to "clean" the data
          File>Maintenance>Reindex (It will prompt to compress when the reindex is done)
8/ Check the data is still good
          File>Maintenance>Check Data
9/ Note the last number in the Audit trail and the last order number in SOP and POP and the last Invoice Number
10/ Open the archive you just made
          File>Open>Company Archive
11/ In the audit trail run one of the audit trail reports form the last number in your good backup, this is a list of what needs to go back in.
12/ Print off new Invoices/SOP and POPs
13/ Send recent INVs/POPS and SOPS to excel so you have a record of what has been posted/added/shipped/received.

14/ Go back to the Live Data
          File>Open>Company Data

Now workout what has changed between backups.  I would start with the Audit Trail, things like Sales Invoices will not need entering manually as you can update the unposted invoices, similarly some invoices may be made by despatching goods on Sales orders and so on.  Work your way through everything and get the balances to match before you start doing any data entry.

Once you are certail that the data is the same and everything is caught up, enable any integrations and restart posting.