What are the step to do physical inventory process?  I want to make zero stock and then upload the actual stock?

First you can use the trn. MI01 there put all the material save, then use T-Code MI04 there you have to enter the count the if you want put 0, put it and make the tick then save then use MI22 post the difference.

About Physical  inventory process you have another way : 
1. Use t-code MI31 instead of using MI01 , it will give you a document number of all your stock.
2. If you did not get the document number use t-code MI24 .
3. MI21 to print  the document.
4. MI04 to enter the count if you want put 0.
5. MI07 post.

Create PI document using MI01 (MI31 -Using Batch)
Enter Count Using MI04 (Select Zero Stock Indicator)
Post Count results using MI07
Check Results using MI24
Upload initial Stock using MB1C 561

Tips by : Phani

Note: For the first initial upload, the best options is to get your abapers to write a simple BDC upload program from the SAP screen mb1c (mvt type 561) using the file type csv (format save in excel).

If you freeze wrongly, you can used MI02 to manually delete the freeze physical inventory documents number.

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