Can’t Opne attachment in Outlook Express

Dear Sir,

I have win 98 installed and outlook exoress 6.
Recently i installed Panda Antivirus Platinum 6.26.
From that time i am not able to open attachments like txt, zip, dbf. I can open attachement like doc files.
When i dounle clik on the message it shows on the top :
OE removed access to the following unsafe attachments in your mail…

I uninstalled Panda but no solution wat to do now ?
Please help me…
Thanks

Amar