Thanks for the response.
For (1), yes, am already specifying the full path to run the external command. Have also tried running in command prompt, the full path command from tomcat installation folder, C:\Program Files\Apache Software Foundation\Tomcat 6.0\, no problem.
For (2), the server has 4GB of physical memory. Made the change as per documentation - "As a rule of thumb set allocations to a ¼ (Initial) and ½ (Maximum) of the physical memory." So its 1GB (Initial) and 2GB (Maximum). Tried again but problem persist.
Anyway, i'm suspecting there could be some issue with the external command which is a piece of licence software to do some conversion as it has ben working and suddenly stopped working. Am working with the tech support of the software to see if we get anywhere. Will update here.
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