This script convert historical data from M1 to M1, M5, M15, M30, H1, H4, D1, W1 and MN, specifying the start date.

This is a basic flow.

1. Download or import your historical data.

2. Close all charts and restart MT4.
3. Menu->File->Open Offline, open an offline chart of the target symbol M1.
*NOTICE* The target offline chart must be marked in grey.
4. Execute "period_converter_all_kai" from the script folder.
5. Enter "Start Date" and press OK.
6. Wait for the message "Converting to period(1), bars to end: 0".
7. Restart MT4 and check all timeframes.

More detailed procedure with picture,

https://www.mql5.com/en/blogs/post/751842