AS mentioned earlier ,you can delte the temp fies also without any issues.
when the defs are first loaded, these are extracted to a temp directory based on the signature type
suppose to get purged but most of the time they remain :(
i have checked other posts too.. in this post IVang has suggested to clear out the corrupted defs by deleting the temp directory..( making sure that i give you the right sugestion :) )
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From the post
Check Ivan suggestion ,
https://www-secure.symantec.com/connect/forums/live-update-failing?page=2
4. Remove the contents of C:\Program Files\SAV\I2_LDVP.VDB (or SYS\SAV\I2_LDVP.VDB on Netware). If there is an I2_LDVP.
TMP folder here, delete the entire .
TMP folder as well as the contents of I2_LDVP.VDB
You can delete them no problem :)
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