Remove all corrupt/infected files from website and re-upload clean files back to site

General information for the website: publish civil society news and articles
Description of requirements/features: Hi,
I have a website which seems to be hacked with corrupt files been added to home directory folder/s.
the website now has been suspended by the hosting co. eukhost til this is resolved. We are advised by eukhost to remove/delete these files and have a backup site version re-uploaded.
thx

this what eukhost wrote to us:

eUKHOST Abuse
17:31 (16 hours ago)

Hello,

We have received the following abuse complaint regarding your services with us.Due to the nature of this complaint, it is imperative that you respond in the next 24 hours. As preventive measure we have suspended your domain ahwazstudies.org
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The infected host name is \"ahwazstudies.org\", and this link has an example of the malicious redirect: \"http://ahwazstudies.org/brawlers.php\"; Depending on the infection type, there may be dozens more malicious redirection pages under ahwazstudies.org.

WARNING As the link is known to malicious, browsing that link is at your own risk.

If ahwazstudies.org is not your host, there is nothing you can do to fix this problem: contact your hoster and have them fix it.

If you are the administrator, searching your web server logs for ahwazstudies.org will likely reveal other copies of these malicious links as well as the command-and-control links (often .php).

One hosting company reported that the malicious script was called \"mainik.php\" and was dropped from Russian IP addresses.

If the problem is not resolved, this will undoubtably get listed again, and runs the risk of having the CBL disallow further removals. So, don\'t just delist the IP and expect it to stay delisted unless the root cause is solved.

In other words, Fix it! or run the risk of self-removals being refused in future listings.
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Also you can refer below link for more information,
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https://sitecheck.sucuri.net/results/ahwazstudies.org
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For resolving this issue please delete all files from the domain and re-upload the website from the clean backup.Also if you are using any CMS and please upgrade it to the latest available version.

If you require any assistance resolving this issue please contact our live support chat for further assistance or reply back to this ticket.

Regards,
Support Department.
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we had the prob before and had it fixed 10 days ago. it was redirected to another source . now it is directed to brawlers.php.
I think all we need is have the unwanted files removed and re-upload the clean files to the server.
it seems all or most these files are .php ; the malware malicious files are php .
the site is asp or aspx

plz let me know how you approach this problem and how long will take to resolve it. all login details to eukhost and access to “Plesk” available on request.
thx
Extra notes: