Formula Error in Maatwebsite/Laravel-Excel

[maherelgamil]

I am used "Maatwebsite/Laravel-Excel" v1.3 for "laravel" 4.2 , but in some cases this error " !H40 -> Formula Error: An unexpected error occured " appeared for me !!

[patrickbrouwers]

Perhaps you have an invalid formula in your file. Do you have precalculate formulas (config('export.calculate')) set to false?

[maherelgamil]

It is really equal false in config file :(

[patrickbrouwers]

It's the content of the cell which is invalid, can you check H40, the cell will contain some error in the formula.

[maherelgamil]

How can i check it ?

[maherelgamil]

thanks for you @patrickbrouwers ,
in data array , i found (=) in and when i remove it , the issue disappear :)