If you get a blank screen when connecting to Box, Dropbox, Google Drive, or OneDrive, one of the causes could be the PHP suhosin extension: https://suhosin.org/stories/index.html.
Suhosin (pronounced ‘su-ho-shin’) is an advanced protection system for PHP installations. It protects servers and users from flaws in PHP applications and the PHP core, both known and unknown. Suhosin divides into two parts that can be used separately or together. The first component is a small patch against the PHP core that implements a few low-level protections against buffer overflows and format string vulnerabilities, while the second component is a powerful PHP extension that implements numerous other safeguards.
To resolve the blank screen issue, change the maximum length of the GET variable. This is via PHP suhosin configuration (php.ini or suhosin.ini). Change:
suhosin.get.max_value_length = 512 (default value)
suhosin.get.max_value_length = 1024
If the above-mentioned solution does not solve the problem, please contact us at firstname.lastname@example.org.