Hi Ragi,
I don't use Newsletter Builder, but are there any differences between the problem install and the others, like:
Is the version of the newsletter plugin the same
Is the version of CMSB the same
Are more (or less) plugins installed or different versions of some plugins?
any mods to the core program that never got copied over?
Any server paths or other variables that never got changed after copying over to the problem install?
Any htaccess file differences or differences in the php ini setup?
Have you tried re-uploading the core program and/or the plugin? (backup first) That has solved some issues for me in the past
Hope one of these offers an ah ha moment...
Best,
Jerry Kornbluth
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