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To investigate the ability for spin-state switching of spin-crossover (SCO) complexes adsorbed to solid substrates, the SCO complex [Fe(H2B(pz)2)2(phenme4)] (pz = pyrazole, phenme4 = 3,4,7,8-tetramethyl-1,10-phenanthroline) is prepared. The new complex is investigated by magnetic susceptibility measurements and Mößbauer spectroscopy in the solid state and by temperature-dependent UV/Vis-spectroscopy in a thin film deposited by physical vapour deposition (PVD) on quartz glass. Thermal and light-induced SCO are observed in the bulk and the film on glass. Submonolayers of this complex obtained by PVD are studied by temperature-dependent near-edge x-ray absorption fine structure (NEXAFS) on Au(111) as well as Bi(111) and by scanning tunneling microscopy (STM) on Au(111). NEXAFS shows thermal and light-induced spin-state switching of the complex on Bi(111), however, with a large temperature-independent high-spin fraction (~ 50%). On the other hand, combined evidence from NEXAFS and STM indicates that on Au(111) the complex dissociates into [Fe(H2B(pz)2)2] and phenme4. Similar observations are made with the parent complex [Fe(H2B(pz)2)2(phen)], which on Bi(111) stays intact and exhibits thermal as well as light-induced SCO, but on Au(111) dissociates into [Fe(H2B(pz)2)2] and phen.