Can I use MD5 emails in the blacklist against my unencrypted lists?

[Papapooch]

Hi guys,
We just got a large suppression file from a vendor that contains MD5 email hashes. I tried searching the forums on "md5" but was told by the search utility the "search string was too short".
I see there are Blacklist settings for allowing MD5 emails but I don't know how the system processes them.

My email lists are NOT in MD5 format. Will MD5 email addresses stop the sending to unhashed email addresses whose MD5 hashes are a match?

Thanks

 

[twisted1919]

Hi,

You can enable md5 for blacklists and then import emails into the blacklist in md5 format.
However, the first thing you should know is that doing so will slow down the checking process considerably, so if you can avoid such usage, avoid id.

My email lists are NOT in MD5 format. Will MD5 email addresses stop the sending to unhashed email addresses whose MD5 hashes are a match?

No, your existing emails will not suffer. When you use md5 in blacklist, we need to has your existing emails and then compare them to the ones from blacklist. This exact process makes things super mega slow as i described above.

 

[Papapooch]

Thanks so much for that explanation my friend. We decided to process the md5 suppression list on our SQL server at the office. Turns out there were 470,000 hashed emails so uploading them to the blacklist was not a good idea.
So we will be uploading the non-hashed emails that matched as a suppression file, to be used in a particular campaign. This will be the first time we have used a suppression list. There were about 15,000 names that matched emails in our Engaged list of 275,000 names. I am assuming that the emails on the suppression list will NOT be added to the blacklist...because they are to be used ONLY for the advertiser we are sending the campaign for.