Hi @Martin McDonnell,
Thank you for posting in this community.
You seem to have an uncommon problem. So, please kindly provide more information below to let us work further.
1.Please make sure that you fulfill the prerequisites for SPMT installation, and then reinstall SPMT.
2.You could try to clear browser cache then restart it.
3.Are other users facing the same problem? View through another computer or account.
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