Deceptive Page Flag in Google Search Console

Technical Details

Forum version : #Invision
Position : Founder
Concerned browser(s) : Google Chrome
Who the problem concerns : All members
When the problem appeared : Upon submitting the forum to Google Search Console
Forum link : https://bgmagic.bulgarianforum.net/

Description of problem

I created this forum (https://bgmagic.bulgarianforum.net) a few weeks ago. I wanted to submit it to Google Search Console in order to get indexed faster and appear in Google searches. However, a few days after I submitted the forum I got a message that it contained "Deceptive pages". The message also stated: "Google has detected harmful content on some of your site’s pages. We recommend that you remove it as soon as possible. Until then, browsers such as Google Chrome will display a warning when users visit or download certain files from your site." According to Google Search Console: "These pages attempt to trick users into doing something dangerous, such as installing unwanted software or revelaing personal information". There is also a "sample url" field but it says "N/A", therefore I don't know which url is a problem for Google.I read on the Google Search Console that deceptive pages means: "The content tries to trick you into doing something you'd only do for a trusted entity — for example, sharing a password, calling tech support, downloading software, or the content contains an ad that falsely claims that device software is out-of-date, prompting users into installing unwanted software". 
You can see this kind of message from Google here too: https://transparencyreport.google.com/safe-browsing/search?url=https:%2F%2Fbgmagic.bulgarianforum.net%2F
I don't have any external links posted on the website. I have checked my computer for viruses, as well as the url. Can this error be caused by ads on the forum? Is there something else which might be causing the problem?
The only thing I can think which I did out of the ordinary in the forum is to add a java scrip to the main page to keep members auto-login in the chatbox. I read about this here: https://help.forumotion.com/t138929-how-can-i-make-users-auto-login-in-new-chatbox. I deleted the script and subbmitted for a review in Google Search Console, but I don't think this fits into the description of deceptive pages given above.
Can you please help me figure this out?

Hello

Usually this can be caused by
A plugin of some kind ( try disable your browser plugins)
An external script
Iframes on certain pages
Harmful javascript
See if you are linking to any site/page which may be harmful by Google

Hello @WizardT

The report seems to be for the whole domain (and therefore all subdomains) because I also get it from the https://www.bulgarianforum.net/ site.

It is certainly a spammer who created a forum on this domain and was flagged. Unfortunately, Google applied the filter to the entire domain. This is one of the weak points of free subdomains...

I just requested a review.

Thanks for the report, I'll let you know.

Hello! Just wanted to let you know that upon my request Google Search Console has reviewed my forum and now it says that it does not contain deceptive pages. I don't know if it is because I removed the script mentioned in my post from the homepage or because @The Godfather solved the issue for the whole bulgarianforum subdomain. Thank you for your help, I really appreciate it!

Hi @WizardT is this now solved ?
If yes please press the mark solved button that can be found at the top of this topic on the left.

Please remember to do this on all topic's when they are solved.

i will mark this as solved,, if it is not please pm me to reopen the thread
thank you

Problem solved & topic archived. Please read our forum rules: ESF General Rules