In Payables while Configuring Financial Options -Inventory Organization field is mandatory. I followed the purchasing videos to create inv org but when I try to create Inv org through Inventory responsiblity in Accounting info- Operating units show no LOV. I saved it without OU. And then switched responsibility to Payables but Payables Financial Options -Inventory org tab also shows no LOV.
Please guide me. Thank you.

The second issue is because of the first one. So lets focus on the first issue. Why you cannot see operating unit on the inventory organization screen.
Please check to which business group you are connected to when you are creating the inventory organization? Is if the same business group to which the operating unit is attached? Check the profile options.

When I create Organization using Inventory responsibility I create a new Organization. Please guide me if I need to use the Business grp already created before creating operating units. Please guide me. I think I am missing some steps. I followed the videos exactly when I created Business grps and created OUs. Thank you.

I followed Video#12 Creating Inventory Organization In Oracle Purchasing to create Inventory organization. I can't find the steps to which Profile option I should assign to Inventory responsibility to get access to Operating Units. I have followed your videos and created OU and Business grps. But please guide me what profile options should I set for Inventory responsibility. Thank you.

Sorry for the late reply.
Let me know the value for "HR: Business Group" profile option for your inventory responsibility and your for Payables responsibility. Both should be pointing to the same Business Group. Also let me know the value at the site level. Thanks.

For Inventory and Payables Responsibility I set the Profile Options HR Security Profile and Business Group to the Business grp I created and was able to see LOV for Operating Unit. But for Inventory Information screen Calendar shows the List of Values contains no entries. Please help me. Thank you.

I was able to create Inventory Organization after I set the Profile Options HR Security and Business grp to the Business grp I created and was also able to attach the Calendar after Creating a workday calendar. Just wanted to let you know that first when I set only Profile option Business group I was not able to access the Organization screen in Inventory so then had to set the profile option for HR Security Profile. Please let me know if my steps to create Inventory Org. were right.
Thank you for all you help.

Yes your steps are correct. Good to know that your problem is resolved.