It's probably the best way to establish the problem and in many cases will fix it.
The other part that's pretty standard, and the answer you'll get from plesk if asked: upgrade to the newest release, which, if this is windows, is 7.5.6 if it's Linux, it's 8.0.1. Either way, 7.5.4 should be upgraded. Since you mention SSH i assume you have linux.
so you have two choices.
upgrade to 7.5.6 to stay at 7, or upgrade to 8.0.1 to be on the cutting edge (I wouldn't recommend this)
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