Problems with formatting data ("General" to "Dates")

Hello!

I often download data from IT system and dates are in "General" format. After that, I normally select the dates and change the format to "Dates". However, when trying to use Pivot Table, I can't group dates into months.

In case I double click every cell for every date, I can use Pivot table and group by month, year, etc. Do you know what might be a solution, instead of clicking each date every time? As the list is really long- 100,000++, I use Autohotkeys to actually double-click every cell and although automatic, it takes hours to complete. Do you know of a more efficient way?

Any comments welcome!

Neori

Thank you very much FDibbins! It worked like magic! You just saved me half of the day waiting!