Sounds like "Generate Accounts" in General Ledger Module --> Utilities Menu --> Generate Accounts is what you are looking for.  Be sure to test and confirm in a Test Company First.  There is no "undo" from this task.  

help-sage100.na.sage.com/.../index.htm

Actually, the undo is to export all the incorrect accounts into Excel, then import into the Delete GL account utility.  Only took a couple hours to remedy for a client.  Regarding test company creation, yes all tables are copied.  Since your only concern is the GL, just copy the GL module into the test.  Shouldn't take TOO long then

Actually, the undo is to export all the incorrect accounts into Excel, then import into the Delete GL account utility.  Only took a couple hours to remedy for a client.  Regarding test company creation, yes all tables are copied.  Since your only concern is the GL, just copy the GL module into the test.  Shouldn't take TOO long then

Thank you!