importdata doen't read the entire txt file

i have a large txt file with 2,609,876 line encoded in ANSI format when i've used the import data command to save it in a matrix , Matlab read the first 400,000 line only . How can i fix this problem. Also i try to encode the file into UTF-8 the same result are get. the data stored in the file are comma delimited such as :

1.050458716,0.010869565,0,0.006993468,6.60E+00,0.115440419,6.077642243,1.13E-08,13.33333333,0.454117523,13.07692308,0.985354563,0.36772478,0.048202102,0.008196767,0.148336301,2
1.050458716,0.058423913,0,0.006993468,6.60E+00,0.115440419,6.077642243,1.13E-08,12.30769231,0.454117523,14.61538462,0.985354563,0.36772478,0.048202102,0.008196767,0.148336301,2

[per isakson]

Have you checked the 400001th row? Could it contain some non-numerical character?