GL no range

Dear All !!!

Anybody can tell me where to create and assign no ranges for GL acccounts... Especially i need to know for recon a/c

Pls help me

While creating customer i m facing the error pasted as below (bold letters) :-

*Reco.Acc 370100 Use Number Range Starts with*

*Message no. ZFIABAP028*

Regards

Kalaivani.J

SAP Fresher