Hi...

I see two things here to improve.

First, show in your search result list which files you are already having in your shared file list. This is done by the SHA1 hash code of the file. Because the hash code is only generated for shared files, it would not be possible to also check it against files in your download folder.
This feature is already on the TODO list and will be implemented soon.

Second, give a warning if you already have a file with the same name in your download destination folder. This would be as a information only, because you can be sure that Phex would never overwrite any files. Anything else would be a BUG.
I checked the source and if you already have a file with the name 'myFilename' Phex should create a new file called '(2)myFilename'.

Do you think this could help you?

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