I spent a long time disentangling the garbled text and had other time commitments, and in the meantime someone else came along and answered with a translation. However, I put hours of work into this thing so here is what I figured out.
SHREE
‘Auspicious; glorious; prosperity; sacred’ — used as honorific with names of deities.
GANESH
Elephant-headed deity traditionally invoked for beginnings. Ganesha literally means ‘lord of the clan’.
VANDANACHUKLAM BARATHARAM
Misspelled with faulty word division. Should be vandana shuklâmbaradharam
‘reverence for the white-clothed’ (shukla ’ white’ + ambara ‘clothed’)
VISHNUMSHASHI VARNAM
‘the all-pervading moon-hare-colored’ (i.e. gray; the Indians see a hare in the moon instead of a man in the moon)
CHATURBHUJAMPRASANNA VADANAM
‘Four-armed, of bright/gracious countenance’.
Again, faulty word division. Should be caturbhujam prasannavadanam
DHYAYETSARVA VIGHNOPA SHANTAYEAGAJANANA PADMARGAM GAJANANAMAHIRSHAM
More faulty word division and misspelling. Should be
dhyâyet ‘meditate’
sarva ‘all’
vighnopashântaye ‘obstacle pacifying’
‘Meditate on him for the removal of all obstacles’
agajânana ‘by the Mountain-Born’ (i.e. Parvati, mother of Ganesha)
padmârkam ‘lotus sunshine’
gajananam ‘the elephant-faced’
aharnisham ‘day and night, continually’
ANEKA DANTAM
Misspelling; should be
aneka-dhâm ‘generously bestowing’
BHAKTANAMEKA DANT! AM
Should be
bhaktânâm ‘the devotees’
ekadântam ‘one tusked’ (Ganesha broke off one of his tusks)
UPASMAHE
‘I salute’?
This mantra is a popular one used by worshipers of Ganesha. However, the person who transcribed the text got it badly corrupted and obviously did not understand what he was writing. It was evidently transliterated into Tamil along the way, because of the confusion of ch/s, t/dh, and k/g that is characteristic of Tamil phonology. You would think that the devotees who believe in this mantra so much as to spam it al over creation would take more care to at least get it accurate.