I've got the same problem and I thought the same thing, i solved the problem reinstalling (copying again the install files and re-run it) IH4. Unfortunately i don't know yet which add-on caused the problem, no error log was ever generate.
A question about uploading, it seem i've some sort of "limit" on the dimension of the files i can upload in IH4, (about 95Kb) if the file is bigger i got a server error message, even if i don't have any server limit set... no error log is generated, no other issue. Where should i look to figure out why is there this limit? (The uploadable size of file is muuuuuuch bigger than 95 kb )
Thanks in advance
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