For older versions of IRRICAD (pre Version 10.5) only:
Autocad 2000 does not like symbols with a name containing &, + or - signs in the dxf files. If you are going to be exporting many designs as dxf files, particularly if you are placing electrical items in the design, it is suggested you change the symbol name so it does not contain any of these symbols. For example, the classic controller symbol is Circle&C. This can be changed to Circle_C (underscore symbol) if you wish. To do this:
1. Start a clean design and use Draw|Symbol to load the Circle&C symbol (uncheck Dynamically size so the symbol comes in at 1in x 1in (2.54cm x 2.54cm)).
2. Explode the symbol, then select everything and select Tools|Create Symbol.
3. Check the Database check box and type in a new name e.g. Circle_C.
4. Open the database and change your controller symbol to be Circle_C instead of Circle&C (click the ... button and browse for the new symbol in the \symbols\database folder). Save the changes.
5. Do this for all items using the Circle&C symbol.
6. Save Changes to close the database.
7. Go back to IRRICAD and make sure the Update Entities from Database check box is checked in Settings|Irrigation Items.
8. Load your design, save the design and close IRRICAD.
9. Re-run IRRICAD and everything will be updated and you can now export the file and import it into Autocad without Autocad complaining.
Note: Do not rename the existing symbol Circle&C. You can delete it after you created a new Circle_C file and replaced it in the database items.