Lots of Temp Files Crashed Server

Hi there,

I rent a dedicated Linux server running two websites. On one of the websites, temp files
keep mounting up and are crashing the server.

The webhost says...
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Your server is overrun with files, and it's proving difficult to find the silver bullet to clear them to free up space for the server to work. We recommend you review the following directories and delete files accordingly:

/var/www/*****
​
It's taking the server an extroadinary amount of time to even show us how many files are in there. If needs be, you should consider deleting that folder and restoring from a backup.
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I'm looking for someone to see what is happening for al the files to accumulate and provide a fix to prevent it from happening in the future.

Thank you for your hellp.