about importing contact csv file

[ashiwebi]

I am new to sugar.I want to import the contact details in my environment but I get this message

Fatal error: Call to a member function read() on a non-object in /home/dev2assi/public_html/crm/modules/Import/ImportCacheFiles.php on line 114

1)I remove the cache directory and again upload the file but same error it is showing.
2)I also upgrade to new version(from 5.1a to 5.2) but no change in the error messages.

How I import my contact details.Thanks in advance for the help.

[ashiwebi]

I got the answer.I replace the cache folder with the original cache from the extracted folder of sugarcrm.